Glibc Helps Hackers Pop Linux – Daily Security Byte EP. 217

Glibc is the standard C library that ships with mosts version of Linux. It includes many functions that handle the common tasks programs might need, such as looking up IP addresses associated with domain names. This week, Google and Red Hat researchers disclosed a serious vulnerability in this common library, which could allow remote attackers to execute code on your Linux machines. Watch today’s Byte to learn more about this issue, and what computers or devices it might affect.

(Episode Runtime: 3:26)

Direct YouTube Link: https://www.youtube.com/watch?v=j72tvt2Pfjk

EPISODE REFERENCES:

• UPDATE: Knowledge Base article describing how WatchGuard products are affected – WatchGuard
• Glibc buffer overflow vulnerability allows code execution  – Google Blogspot
• Red Hat patch advisory for glibc vulnerability – Sourceware.org
• Proof of Concept exploit for the glibc bug – Github
• Article covering the Linux glibc issue – The Register

— Corey Nachreiner, CISSP (@SecAdept)

A Dozen Microsoft Updates – Daily Security Byte EP. 174

If you use Microsoft or Adobe products—as the majority of computer users do—it’s that time again… Patch Day.

For November’s Patch Day, Microsoft released a dozen bulletins fixing many flaws in their most popular products. Watch today’s video for the quick highlights about these and Adobe’s updates.

UPDATE: As gung-ho as I am about applying patches quickly, there have been reports that some of the Windows 10 updates can cause problems. You may want to test these updates before deploying them throughout your network.

(Episode Runtime: 1:43)

Direct YouTube Link: https://www.youtube.com/watch?v=xGj2grkLQfk

EPISODE REFERENCES:

• Microsoft Patch Day Summary for November 2015 – Microsoft
• Adobe Flash bulletin for November 2015 – Abode
• Two new Microsoft security advisories for November – Microsoft

— Corey Nachreiner, CISSP (@SecAdept)

Lenovo Security Fail – Daily Security Byte EP.78

A few months ago, some of Lenovo’s preinstalled adware got them into security hot water. Looks like their pre-installed software has struck again. Watch today’s video to learn about the latest Lenovo vulnerabilities and what you can do about them.

 

(Episode Runtime: 1:54)

Direct YouTube Link: https://www.youtube.com/watch?v=2jU2b42iVY4

EPISODE REFERENCES:

• Security advisory detail three new Lenovo Software Update flaws – IOActive
• Article about the latest Lenovo security fail – Gizmodo

— Corey Nachreiner, CISSP (@SecAdept)

Latest Flash Update Plugs 18 Security Holes

Do you watch a lot of online video or play interactive web games? Perhaps your organization uses rich, interactive web-based business applications? In either case, you’ve probably installed Adobe Flash, along with the  500 million other device holders who use it. In this case, you better update Flash as soon as you can.

During Microsoft Patch day, Adobe released a security bulletin describing 18 vulnerabilities in the popular rich media web plug-in. There’s no point in covering the flaws individually, as the majority of them share the same scope and impact. In short, most of the flaws involve memory corruption issues that a smart attacker could leverage to execute code on your PC. The attacker would only have to entice you to a web site containing malicious code. In other words, most of them help attackers setup drive-by download attacks.

Though it doesn’t appear attackers are exploiting any of these flaws in the wild yet, Adobe rates there severity a “Priority 1” for Windows and Mac users. This means you should patch within 72 hours. If you use Flash, go get the latest version, and check out Adobe’s security bulletin if you’d like more details. — Corey Nachreiner, CISSP (@SecAdept)

Adobe Patches Flash but Delays Reader Update

Summary:

• This vulnerability affects: Adobe Flash Player running on all platforms and Adobe Air
• How an attacker exploits it: By enticing users to visit a website containing malicious Flash content
• Impact: In the worst case, an attacker can execute code on the user’s computer, potentially gaining control of it
• What to do: Download and install the latest version of Adobe Flash Player for your platform

Exposure:

Adobe Flash Player displays interactive, animated web content called Flash. Although Flash is optional, 99% of PC users download and install it to view multimedia web content. It runs on many operating systems, including mobile operating systems like Android.

In a security bulletin released this week during Patch Day, Adobe released an update that fixes a dozen security vulnerabilities affecting Flash Player running on any platform. The bulletin doesn’t describe the flaws in much technical detail, but does say most of them consist of various types of memory corruption flaws. If an attacker can entice one of your users to visit a malicious website containing specially crafted Flash content, he could exploit many of these vulnerabilities to execute code on that user’s computer, with that user’s privileges. If your Windows users have local administrator privileges, an attacker could exploit this flaw to gain full control of their PCs.

Though attackers aren’t exploiting these flaws in the wild yet, Adobe rates them as a “Priority 1” issues for Windows, Mac, and Linux users, and recommends you apply the updates within 72 hours. These vulnerabilities also affect other platforms as well, though not as severely. I recommend you update any Flash capable device as soon as you can.

As an aside, though Adobe promised a Reader update this month, they seem to have delayed it for some reason. You may want to keep an eye on Adobe’s Security page for more updates.

Solution Path

Adobe has released new versions of Flash Player to fix these issues. If you allow Adobe Flash in your network, you should download and install the new versions immediately. If you’ve enabled Flash Player’s recent “silent update” option, you will receive this update automatically.

You can download Flash for your computer at the link provided below. See the bulletin’s “Affected Software” section for more details on getting Flash updates for other platforms:

Keep in mind, if you use Google Chrome or Internet Explorer 10 or 11 you’ll have to update it separately.

For All WatchGuard Users:

If you choose, you can configure the HTTP proxy on your XTM appliance to block Flash content. Keep in mind, doing so blocks all Flash content, whether legitimate or malicious.

Our proxies offer many ways for you to block files and content, including by file extension, MIME type, or by using very specific hexidecimal patterns found in the body of a message – a technique sometimes referred to as Magic Byte detection. Below I list the various ways you can identify various Flash files:

File Extension:

• .flv –  Adobe Flash file (file typically used on websites)
• .fla – Flash movie file
• .f4v – Flash video file
• .f4p – Protected Flash video file
• .f4a – Flash audio file
• .f4b – Flash audiobook file

MIME types:

• video/x-flv
• video/mp4 (used for more than just Flash)
• audio/mp4 (used for more than just Flash)

FILExt.com reported Magic Byte Pattern:

• Hex FLV: 46 4C 56 01
• ASCII FLV: FLV
• Hex FLA:  D0 CF 11 E0 A1 B1 1A E1 00

(Keep in mind, not all the Hex and ASCII patterns shared here are appropriate for content blocking. If the pattern is too short, or not unique enough, blocking with them could result in many false positives) 

If you decide you want to block Flash files, the links below contain instructions that will help you configure your Firebox proxy’s content blocking features using the file and MIME information listed above.

• XTM Appliance with WSM 11.x
  • How do I block files with the FTP proxy?
  • How do I block files with the HTTP proxy?
  • How do I block files with the POP3 proxy?
  • How do I block files with the SMTP Proxy?

• Firebox X Edge running 10.x
  • How do I block files with the FTP proxy?
  • How do I block files with the HTTP proxy?
  • How do I block files with the POP3 proxy?
  • How do I block files with the SMTP proxy

• Firebox X Core and X Peak running Fireware 10.x
  • How do I block files with the FTP proxy?
  • How do I block files with the HTTP proxy?
  • How do I block files with the POP3 proxy?
  • How do I block files with the SMTP proxy?

Status:

Adobe has released updates to fix these Flash vulnerabilities.

References:

• September 2014 Adobe Flash Security Bulletin

This alert was researched and written by Corey Nachreiner, CISSP (@SecAdept)

Office Patches Mend SharePoint and OneNote

Severity: High

Summary:

• These vulnerabilities affect: Microsoft Office related products like OneNote and SharePoint Server
• How an attacker exploits them: Varies. Typically by enticing users to open or interact with maliciously crafted Office documents
• Impact: Many. In the worst case, an attacker can gain complete control of your Windows computer
• What to do: Install the appropriate Microsoft patches as soon as possible, or let Windows Automatic Update do it for you

Exposure:

Today, Microsoft released two security bulletins that fix a like number of vulnerabilities in OneNote and SharePoint. We summarize these security bulletins below, in order from highest to lowest severity.

• MS14-048: OneNote Code Execution Vulnerability
  

OneNote is a collaborative, multiuser note taking application that ships with Office. It suffers from an unspecified vulnerability having to do with how it handles specially crafted OneNote files. If an attacker can lure you into opening such a file, she could exploit this flaw to execute code on your computer, with you privileges. As usual, if you are a local administrator, the attacker gains complete control of your PC.

Microsoft rating: Important

• MS14-050: SharePoint Elevation of Privilege Vulnerability

SharePoint Server is Microsoft’s web and document collaboration and management platform. It suffers from a privilege escalation vulnerability. SharePoint offers an extensibility model that allows you to create apps that can access and use SharePoint resources. However, SharePoint suffers some unspecified flaw that allows specially crafted apps to bypass permission management. In short, by running a specially crafted application, an attacker may be able to access all the SharePoint resources of the currently logged-in user.

Microsoft rating: Important

Solution Path:

Microsoft has released Office and SharePoint-related patches that correct these vulnerabilities. You should download, test, and deploy the appropriate updates throughout your network as soon as possible. If you choose, you can also let Windows Update automatically download and install these updates for you.

Keep in mind, however, that we highly recommend you test updates before running them in your production environment; especially updates for critical production servers.

The links below point directly to the “Affected and Non-Affected Software” section of each bulletin, where you can find all of Microsoft’s update links:

• MS14-048
• MS14-050

For All WatchGuard Users:

We recommend you install Microsoft’s updates to completely protect yourself from these flaws.

Status:

Microsoft has released patches correcting these issues.

References:

• Microsoft Security Bulletin MS14-048
• Microsoft Security Bulletin MS14-050

This alert was researched and written by Corey Nachreiner, CISSP (@SecAdept).

---

What did you think of this alert? Let us know at your.opinion.matters@watchguard.com.

Office Updates Include Patches for SharePoint Vulnerabilities

Severity: High

Summary:

• These vulnerabilities affect: Microsoft Office and related products like SharePoint Server
• How an attacker exploits them: Varies. Typically by enticing users to open or interact with maliciously crafted Office documents, or interacting with web resources
• Impact: Many. In the worst case, an attacker can gain complete control of your Windows computer
• What to do: Install the appropriate Microsoft patches as soon as possible, or let Windows Automatic Update do it for you

Exposure:

Today, Microsoft released three security bulletins that fix a number of vulnerabilities in Office, SharePoint, and related components. We summarize these security bulletins below, in order from highest to lowest severity.

• MS14-022: Multiple SharePoint Vulnerabilities

SharePoint Server is Microsoft’s web and document collaboration and management platform. SharePoint, and some of its related components, suffer from both multiple remote code execution vulnerabilities and a cross-site scripting (XSS) flaw. The remote code execution flaws pose the most risk, and involve several unspecified input sanitation vulnerabilities in a number of SharePoint pages. If an authenticated attacker can upload specially crafted content to your SharePoint server, he could leverage this flaw to execute code on that server with the W3WP (w3wp.exe) service account’s privileges. Unfortunately, Microsoft’s alert doesn’t go into detail about the privileges associated with the W3WP services account. However, we’ve found that w3wp.exe often runs as a child process under svchost.exe, which runs with local SYSTEM privileges by default; potentially making this a complete system compromise. If you run SharePoint servers, you should patch this as quickly as you can.

Microsoft rating: Critical

• MS14-023: Office Remote Code Execution Flaw
  

Various Office components suffer from two publicly reported vulnerabilities. The worst is a remote code execution flaw involving the way Office’s “Grammar Checker” feature loads Dynamic Link Libraries (DLL). However, the flaw only affects Grammar Checker when the language is set to Chinese (Simplified). If a remote attacker can convince you to open an Office document that resides in the same directory (local or over a network) as a malicious DLL, she could exploit this flaw to execute code with your privileges. If you have local administrative access, the attacker gains complete control of your computer. However, this flaw will likely primarily affect Chinese Office users, which somewhat limits its impact. Office also suffers from something call a “token reuse” flaw, but it poses a lesser risk that the remote code execution one.

Microsoft rating: Important

• MS13-086:  MCCOMCTL ASLR Bypass Vulnerabilities
  

Office (and many other Microsoft products) ships with a set of ActiveX controls that Microsoft calls the Windows Common Controls (MSCOMCTL.OCX). Address Space Layout Randomization (ASLR) is a memory obfuscation technique that some operating systems use to make it harder for attackers to find specific things in memory, which in turn makes it harder for them to exploit memory corruption flaws. Office’s MSCOMCTL component doesn’t enable ASLR protection. This means attackers can leverage this particular component to bypass Windows’ ASLR protection features. This flaw alone doesn’t allow an attacker to gain access to your Windows computer. Rather, it can help make other memory corruption vulnerabilities easier to exploit. This update fixes the ASLR bypass hole.

Microsoft rating: Important

Solution Path:

Microsoft has released Office and SharePoint-related patches that correct all of these vulnerabilities. You should download, test, and deploy the appropriate updates throughout your network as soon as possible. If you choose, you can also let Windows Update automatically download and install these updates for you.

Keep in mind, however, that we highly recommend you test updates before running them in your production environment; especially updates for critical production servers.

The links below point directly to the “Affected and Non-Affected Software” section of each bulletin, where you can find all of Microsoft’s update links:

• MS14-022
• MS14-023
• MS14-024

For All WatchGuard Users:

WatchGuard’s eXtensible Threat Management (XTM) security appliances can help mitigate the risk of some of these vulnerabilities. Gateway Antivirus and Intrusion Prevention services can often prevent some of these types of attacks, or the malware these types of attacks try to distribute. Nonetheless, we still recommend you install Microsoft’s updates to completely protect yourself from these flaws.

Status:

Microsoft has released patches correcting these issues.

References:

• Microsoft Security Bulletin MS14-022
• Microsoft Security Bulletin MS14-023
• Microsoft Security Bulletin MS14-024

This alert was researched and written by Corey Nachreiner, CISSP (@SecAdept).

---

What did you think of this alert? Let us know at your.opinion.matters@watchguard.com.

UPDATE TO: Advanced Attackers Exploit IE 0day in the Wild

Severity: High

Summary:

• This vulnerability affects: All versions of Internet Explorer (IE)
• How an attacker exploits it: By enticing a user to visit web site containing malicious content
• Impact: An attacker can execute code with your privileges, potentially gaining complete control of your computer
• What to do: Install Microsoft’s emergency IE patch immediately, or let Windows Update do it for you

Exposure:

On Monday, we released an alert warning about a zero day vulnerability affecting all version of Internet Explorer. Researchers discovered attackers exploiting this critical flaw in the wild, and Microsoft had not yet released a patch at that time.

Today, Microsoft released an out-of-cycle security bulletin containing an update to fix this serious vulnerability. As mentioned in our original alert, IE suffers from something called a “use after free” memory corruption vulnerability. By enticing one of your users to a web site containing malicious content, an attacker can exploit this flaw to execute code on your machine, with your privileges. As usual, if you have local administrator privileges, the attacker gains full control of your machine.

Keep in mind, today’s attackers often hijack legitimate web pages and booby-trap them with malicious code. Typically, they do this via hosted web ads or through SQL injection and cross-site scripting (XSS) attacks. Even recognizable and authentic websites could pose a risk to your users if hijacked in this way, and the vulnerabilities described in today’s bulletin are perfect for use in drive-by download attacks. Furthermore, attackers are already exploiting this particular flaw in targeted attacks. We highly recommend you install Microsoft’s IE update immediately

We have included the original alert below for your convenience.

Solution Path:

Microsoft has released IE updates to correct this vulnerability. You should download, test, and deploy the updates immediately, or let Windows Update do it for you. You can find the updates in the “Affected and Non-Affected Software” section of Microsoft’s IE bulletin. Also note, Microsoft has included updates for Windows XP customers, despite their End-of-Life date last month.

If for some reason you cannot patch immediately, there are also some workarounds than can mitigate the issue. We detail those workarounds in our original alert, which we’ve included below for your convenience.

For All WatchGuard Users:

As mentioned in our original alert, there are a number of things WatchGuard XTM customers can do to protect themselves. For instance, you can use our proxy policies to block Flash content by extension (.SWF) or by MIME type (application/x-shockwave-flash). Furthermore, our IPS service includes signatures that block this IE exploit (update to signature set 4.410). Nonetheless, we still highly recommend you install Microsoft’s IE update to completely protect yourself from this attack.

Status:

Microsoft has released patches to fix this vulnerability.

References:

• MS Security Bulletin MS14-021

This alert was researched and written by Corey Nachreiner, CISSP (@SecAdept).

---

Over the weekend, Microsoft released a critical security advisory warning customers of a serious new zero day vulnerability in Internet Explorer (IE), which attackers are exploiting in the wild. Around the same time, Kaspersky also noted an attack campaign leveraging a new Adobe Flash zero day flaw, which Adobe patched today. I’ll discuss both issues below, starting with the IE issue.

IE Zero Day in the Wild

According to this blog post, researchers at FireEye discovered advanced attackers exploiting this zero day IE flaw as part of a persistent attack campaign they are calling “Operation Clandestine Fox.” The attack targets IE 9-11 and also leverages a Flash flaw to help bypass some of Windows’ security features.

Shortly after FireEye’s post, Microsoft released a security advisory confirming the previously undiscovered flaw in IE. The advisory warns that the flaw affects all versions of IE (though the attack seems to target IE 9-11). While Microsoft is still researching the issue, the vulnerability seems to be a “use after free” class of memory corruption vulnerability. In short, if an attacker can entice you to a web page containing maliciously crafted content, he could exploit this flaw to execute code on your machine, with your privileges. As usual, if you have local administrator privileges, the attacker would gain full control of your machine. It’s interesting to note, the attackers also leverage a known Adobe Flash issue to help defeat some of Microsoft’s Windows memory protection features.

Zero day IE vulnerabilities are relatively rare, and very dangerous. Attackers are already exploiting this IE one in the wild, so it poses a significant risk. Unfortunately, Microsoft just learned of the flaw, so they haven’t had time to patch it yet. I suspect Microsoft will release an out-of-cycle patch for this flaw very shortly since this is a high-profile issue. In the meantime here a few workarounds to help mitigate the flaw:

• Temporarily use a different web browser – I’m typically not one to recommend one web browser over another, as far as security is concerned. They all have had vulnerabilities. However, this is a fairly serious issue.  So you may want to consider temporarily using a different browser until Microsoft patches.
• Install Microsoft EMET – EMET is an optional Microsoft tool that adds additional memory protections to Windows. I described EMET in a previous episode of WatchGuard Security Week in Review. Installing EMET could help protect your computer from many types of memory corruption flaws, including this one. This Microsoft blog post shares more details on how it can help with this issue.
• Configure Enhanced Security Configuration mode on Windows Servers – Windows Servers in Enhanced Security Configuration mode are not vulnerable to many browser-based attacks.
• Disable VML in IE – This exploit seems to rely on VML to work. Microsoft released a blog post detailing how disabling VML in IE, or running IE in “Enhanced Protection Mode” can help.
• Make sure your AV and IPS is up to date – While not all IPS and AV systems have signatures for all these attacks yet, they will in the coming days. In fact, WatchGuard’s IPS engineers have already created signatures to catch this attack. We are QA testing the signatures now, but they should be available to XTM devices shortly. Whatever IPS system you use, be sure to keep your AV and IPS systems updating regularly, to get the latest protections.
• WatchGuard XTM customers can block Flash with proxies – If you own a WatchGuard XTM security appliance, you can use our proxy policies to block certain content, including Flash content. For instance, you can use our SMTP or HTTP proxies to block SWF files by extensions (.SWF) or by MIME type (application/x-shockwave-flash). Keep in mind, blocking Flash blocks both legitimate and malicious content. So only implement this workaround if you are ok with your users not accessing normal Flash pages.

Adobe Patches Flash Zero Day

Coincidentally, Adobe also released an emergency Flash update today fixing a zero day exploit that other advanced attackers are also exploiting in a targeted watering hole campaign. The patch fixes a single vulnerability in the popular Flash media player, which attackers could exploit to run arbitrary code on your system; simply by enticing you to a web site containing specially crafted Flash content. This exploit was discovered in the wild by Kaspersky researchers (one of our security partners). According to Kaspersky’s research, the exploit was discovered on a Syrian website, and seems to be designed to target potential Syrian dissidents.

The good news is there is a patch for this flaw. So if you use Adobe Flash, go get the latest update now. By the way, some browsers like Chrome and IE 11 embed Flash directly, so you will also have to update those browsers individually. Finally, though the IE zero day I mentioned earlier does rely on a Flash issue, this particular zero day Flash flaw is totally unrelated. One additional note; WatchGuard’s IPS engineers have also created a signature for this exploit as well. It will be available shortly, once testing is complete.

So to summarize, if you use IE, disable VML, install EMET, and watch for an upcoming patch. If you use Flash, updates as soon as you can. I will be sure to inform you here, as soon as Microsoft releases their real patch or FixIt. — Corey Nachreiner, CISSP (@SecAdept)

Advanced Attackers Exploit IE & Flash 0days in the Wild

Over the weekend, Microsoft released a critical security advisory warning customers of a serious new zero day vulnerability in Internet Explorer (IE), which attackers are exploiting in the wild. Around the same time, Kaspersky also noted an attack campaign leveraging a new Adobe Flash zero day flaw, which Adobe patched today. I’ll discuss both issues below, starting with the IE issue.

IE Zero Day in the Wild

According to this blog post, researchers at FireEye discovered advanced attackers exploiting this zero day IE flaw as part of a persistent attack campaign they are calling “Operation Clandestine Fox.” The attack targets IE 9-11 and also leverages a Flash flaw to help bypass some of Windows’ security features.

Shortly after FireEye’s post, Microsoft released a security advisory confirming the previously undiscovered flaw in IE. The advisory warns that the flaw affects all versions of IE (though the attack seems to target IE 9-11). While Microsoft is still researching the issue, the vulnerability seems to be a “use after free” class of memory corruption vulnerability. In short, if an attacker can entice you to a web page containing maliciously crafted content, he could exploit this flaw to execute code on your machine, with your privileges. As usual, if you have local administrator privileges, the attacker would gain full control of your machine. It’s interesting to note, the attackers also leverage a known Adobe Flash issue to help defeat some of Microsoft’s Windows memory protection features.

Zero day IE vulnerabilities are relatively rare, and very dangerous. Attackers are already exploiting this IE one in the wild, so it poses a significant risk. Unfortunately, Microsoft just learned of the flaw, so they haven’t had time to patch it yet. I suspect Microsoft will release an out-of-cycle patch for this flaw very shortly since this is a high-profile issue. In the meantime here a few workarounds to help mitigate the flaw:

• Temporarily use a different web browser – I’m typically not one to recommend one web browser over another, as far as security is concerned. They all have had vulnerabilities. However, this is a fairly serious issue.  So you may want to consider temporarily using a different browser until Microsoft patches.
• Install Microsoft EMET – EMET is an optional Microsoft tool that adds additional memory protections to Windows. I described EMET in a previous episode of WatchGuard Security Week in Review. Installing EMET could help protect your computer from many types of memory corruption flaws, including this one. This Microsoft blog post shares more details on how it can help with this issue.
• Configure Enhanced Security Configuration mode on Windows Servers – Windows Servers in Enhanced Security Configuration mode are not vulnerable to many browser-based attacks.
• Disable VML in IE – This exploit seems to rely on VML to work. Microsoft released a blog post detailing how disabling VML in IE, or running IE in “Enhanced Protection Mode” can help.
• Make sure your AV and IPS is up to date – While not all IPS and AV systems have signatures for all these attacks yet, they will in the coming days. In fact, WatchGuard’s IPS engineers have already created signatures to catch this attack. We are QA testing the signatures now, but they should be available to XTM devices shortly. Whatever IPS system you use, be sure to keep your AV and IPS systems updating regularly, to get the latest protections.
• WatchGuard XTM customers can block Flash with proxies – If you own a WatchGuard XTM security appliance, you can use our proxy policies to block certain content, including Flash content. For instance, you can use our SMTP or HTTP proxies to block SWF files by extensions (.SWF) or by MIME type (application/x-shockwave-flash). Keep in mind, blocking Flash blocks both legitimate and malicious content. So only implement this workaround if you are ok with your users not accessing normal Flash pages.

Adobe Patches Flash Zero Day

Coincidentally, Adobe also released an emergency Flash update today fixing a zero day exploit that other advanced attackers are also exploiting in a targeted watering hole campaign. The patch fixes a single vulnerability in the popular Flash media player, which attackers could exploit to run arbitrary code on your system; simply by enticing you to a web site containing specially crafted Flash content. This exploit was discovered in the wild by Kaspersky researchers (one of our security partners). According to Kaspersky’s research, the exploit was discovered on a Syrian website, and seems to be designed to target potential Syrian dissidents.

The good news is there is a patch for this flaw. So if you use Adobe Flash, go get the latest update now. By the way, some browsers like Chrome and IE 11 embed Flash directly, so you will also have to update those browsers individually. Finally, though the IE zero day I mentioned earlier does rely on a Flash issue, this particular zero day Flash flaw is totally unrelated. One additional note; WatchGuard’s IPS engineers have also created a signature for this exploit as well. It will be available shortly, once testing is complete.

So to summarize, if you use IE, disable VML, install EMET, and watch for an upcoming patch. If you use Flash, updates as soon as you can. I will be sure to inform you here, as soon as Microsoft releases their real patch or FixIt. — Corey Nachreiner, CISSP (@SecAdept)

Latest Flash Update Mends Four Flaws

Summary:

• This vulnerability affects: Adobe Flash Player running on all platforms and Adobe Air
• How an attacker exploits it: By enticing users to visit a website containing malicious Flash content
• Impact: In the worst case, an attacker can execute code on the user’s computer, potentially gaining control of it
• What to do: Download and install the latest version of Adobe Flash Player for your platform

Exposure:

Adobe Flash Player displays interactive, animated web content called Flash. Although Flash is optional, 99% of PC users download and install it to view multimedia web content. It runs on many operating systems, including mobile operating systems like Android.

This week, Adobe released a security bulletin describing four security vulnerabilities (based on CVE numbers) that affect Flash Player running on any platform. It doesn’t describe the flaws in much technical detail, other than saying they consist mostly of buffer overflow vulnerabilities and other types of memory corruption flaws (and a cross-site scripting issue). That said, Adobe does warn that if an attacker can entice one of your users to visit a malicious website containing specially crafted Flash content, he could exploit many of these unspecified vulnerabilities to execute code on that user’s computer, with that user’s privileges. If your Windows users have local administrator privileges, an attacker could exploit this flaw to gain full control of their PCs.

Though it doesn’t look like attackers are exploiting these flaws in the wild yet, Adobe rates the flaws as a “Priority 1” issues for Windows and Macintosh users, and recommends you apply the updates within 72 hours. These vulnerabilities also affect other platforms as well, such as Internet Explorer (IE) 11 and Chrome. I recommend you update any Flash capable platform as soon as you can.

Solution Path

Adobe has released new versions of Flash Player to fix these issues. If you allow Adobe Flash in your network, you should download and install the new versions immediately. If you’ve enabled Flash Player’s recent “silent update” option, you will receive this update automatically.

You can download Flash for your computer at the link provided below. See the bulletin’s “Affected Software” section for more details on getting Flash updates for other platforms:

Keep in mind, if you use Google Chrome or IE 11, you’ll have to update it seperately.

For All WatchGuard Users:

Good News! WatchGuard’s Gateway Antivirus and Intrusion Prevention services can often prevent these sorts of attacks, or the malware they try to distribute. For instance, our IPS signature team has developed signatures that can detect and block many of the memory corruption vulnerabilities described in Adobe’s alert:

• WEB  Adobe Flash Player High Surrogate Parsing Cross Site Scripting  (CVE-2014-0509)
• WEB-CLIENT Adobe Flash Player Information Disclosure (CVE-2014-0508)
• EXPLOIT Adobe Flash Player Memory Corruption (CVE-2014-0506)
• EXPLOIT Adobe Flash Player Memory Corruption (CVE-2014-0507)

Your XTM appliance should get this new IPS update shortly.

Furthermore, our Reputation Enabled Defense (RED) and WebBlocker services can often prevent your users from accidentally visiting malicious (or legitimate but booby-trapped) web sites that contain these sorts of attacks. Nonetheless, we still recommend you install Adobe’s Flash update to completely protect yourself from all of these flaws.

Status:

Adobe has released updates to fix these Flash vulnerabilities.

References:

• April 2014 Adobe Flash Security Bulletin

This alert was researched and written by Corey Nachreiner, CISSP (@SecAdept)