To avoid exploits of the critical new Microsoft VML vulnerability (#1), users should be told to read email in plain text mode only. And multiple critical buffer overflow vulnerabilities have been found in CA BrightStor ARCserve (#2). Many people don't focus on vulnerabilities in the backup servers, to their great misfortune. The bad guys are sharply focused on exploiting backup servers; they hold lots of valuable data and they give the bad guys an easy path into other sensitive systems.
@RISK is the SANS community's consensus bulletin summarizing the most important vulnerabilities and exploits identified during the past week and providing guidance on appropriate actions to protect your systems (PART I). It also includes a comprehensive list of all new vulnerabilities discovered in the past week (PART II).
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SECURITY TRAINING UPDATE: Several of the hands-on immersion security training courses at SANS 2007 (San Diego, March 29 - April 4) are starting to fill up. If you want a place, register early. You'll also save hundreds of dollars if you do it in the next few weeks. Full Schedule (53 courses): http://www.sans.org/sans2007/event.php
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Part I for this issue has been compiled by Rob King and Rohit Dhamankar at TippingPoint, a division of 3Com, as a by-product of that company's continuous effort to ensure that its intrusion prevention products effectively block exploits using known vulnerabilities. TippingPoint's analysis is complemented by input from a council of security managers from twelve large organizations who confidentially share with SANS the specific actions they have taken to protect their systems. A detailed description of the process may be found at http://www.sans.org/newsletters/cva/#process
Description: The Microsoft Vector Markup Language (VML) parser contains an integer overflow vulnerability in the way it parses VML data. VML is used to describe complex vector-based graphics and other documents. The VML parser is used by Internet Explorer, and is believed to also be used by Outlook, Outlook Express, and Microsoft Office. A specially-crafted VML document could exploit this vulnerability to execute arbitrary code with the privileges of the current user. VML documents are automatically rendered in Microsoft Internet Explorer and Microsoft Outlook Express. A working exploit is available to the members of Immunity's partners' program. According to the Microsoft advisory, this flaw is being actively exploited.
Status: Microsoft confirmed, updates available. Users are advised to read email in plain text mode only, as this will eliminate the email attack vector. Additionally, users can mitigate the impact of this vulnerability by unregistering the "vgx.dll" system component, using the command '"%SystemRoot%\System32\regsvr32.exe" -u "%CommonProgramFiles%\Microsoft Shared\VGX\vgx.dll"'. Microsoft's security bulletin provides other mitigating strategies.
Council Site Actions: All reporting council sites are responding to this issue. They all plan to deploy the patch during their next regularly scheduled maintenance cycle.
Description: Computer Associates BrightStor ARCserve Backup products provide backup services for Windows platform. The product contains multiple buffer overflow vulnerabilities: (a) The BrightStor ARCserve Tape Engine service, which listens on port 6502/tcp by default, contains two buffer overflows that can be triggered by specially crafted RPC calls. These flaws can be exploited to execute arbitrary code with "SYSTEM/root" privileges. Exploit code has been publicly posted. (b) The BrightStor ARCserve Message Engine RPC service, which listens on port 6503/tcp and 6504/tcp by default, contains two buffer overflows that can be triggered by specially crafted RPC calls. The flaws can be exploited to execute arbitrary code with "SYSTEM/root" privileges. The technical details required to craft an exploit have been posted. (c) The BrightStor ARCserve Mediaserv RPC service contains two buffer overflows that can be triggered by specially crafted RPC calls. The flaws can be exploited to execute arbitrary code with "SYSTEM/root" privileges. Limited technical details have been publicly posted.
Status: CA has issued updates that resolve all the buffer overflow vulnerabilities. Users are advised to block access to ports 6502/tcp, 6503/tcp and 6504/tcp at the network perimeter to prevent external attacks. CERT has seen an increased scanning activity for port 6502/tcp and is aware of active exploitation of the Tape Engine overflow vulnerability. Special Note: CA BrightStor ARCServe buffer overflows have been actively exploited for the past couple of years. SANS recommends that you block all the ports that are opened by the software, at the network perimeter. A list of the ports to block may be found at: http://www.ca.com/at/local/partner/techtalk_mar05_faq.pdf http://supportconnectw.ca.com/public/ca_common_docs/brightstorwinxpsp2matrix.asp
Description: Microsoft Excel contains multiple vulnerabilities in the parsing of Excel spreadsheet files. A specially-crafted Excel file containing a malformed record or string could exploit one of these vulnerabilities and allow arbitrary code execution with the privileges of the current user. Currently, no technical details or exploits for these vulnerabilities are known to be publicly available. Note that Office 2003 and later versions do not open Excel documents without user prompting; hence, they affected to a lesser extent.
Status: Microsoft confirmed, updates available.
Council Site Actions: All reporting council sites are responding to this issue. They all plan to deploy the patch during their next regularly scheduled maintenance cycle.
Description: Adobe Acrobat Reader contains a heap memory corruption vulnerability. A specially-crafted PDF file could exploit this vulnerability and overwrite a function pointer, allowing attackers to execute arbitrary code with the privileges of the current user. PDF files are generally configured to open without prompting on most platforms. The technical details for this vulnerability are publicly available.
Status: Adobe confirmed, updates available.
Description: Apple Mac OS X contains two flaws in the handling of Mac OS X Disk Image (DMG) files. These files store an embedded filesystem and are used to transfer data and applications. The first vulnerability stems from the way Finder (the default graphical shell and file management application) handles volume names in DMG files. A specially-crafted volume name in a DMG file could exploit this vulnerability and execute arbitrary code with the privileges of the current user. The second vulnerability stems from an integer overflow in the kernel code used for handling Fast File System (FFS) volumes. A specially-crafted DMG file containing an FFS image could exploit this vulnerability and execute arbitrary code with root privileges. Note that DMG files are automatically opened by default in Apple Safari. The technical details and proofs-of-concept are publicly available for these vulnerabilities.
Status: Apple has not confirmed, no updates available. Users can mitigate the impact of these vulnerabilities by disabling the "Open Safe Files" option in Safari's configuration. Council Site Status: Only one of the report council sites is using the affected software. They plan to deploy the patch when one is available. In the meantime, they have advised their Safari users to disable the "open safe files" feature.
Description: Microsoft Outlook contains the following vulnerabilities:
Status: Microsoft confirmed, updates available.
Council Site Actions: All reporting council sites are responding to this issue. They all plan to deploy the patch during their next regularly scheduled maintenance cycle.
Description: kadmind provides remote administrative access to the Kerberos authentication database, and runs on the Key Distribution Center (KDC) server of a Kerberos realm. The kadmind daemon contains two vulnerabilities that can be exploited by unauthenticated attackers to execute arbitrary code with typically root privileges. The problems occur due to the way kadmind handles initializing and freeing certain pointers. Note that any third party software using the MIT Kerberos GSS-API or RPC library may also be vulnerable.
Status: MIT Kerberos has released patches for these issues. The fixes will be included in the upcoming releases.
Description: HP OpenView Network Node Manager (NNM), HP's enterprise management product, contains a remote code execution vulnerability. An attacker could exploit this vulnerability to execute arbitrary code with the privileges of the NNM server process. No technical details are believed to be publicly available for this exploit. NNM on HP-UX, Solaris, Microsoft Windows, and Linux is vulnerable.
Status: HP confirmed, updates available.
Description: The Microsoft Office 2003 Brazilian Portuguese Grammar Checker contains a memory corruption vulnerability. A specially-crafted document opened in a vulnerable version of Microsoft Office with this component installed could exploit this vulnerability and execute arbitrary code with the privileges of the current user. Note that Microsoft Office 2003 does not automatically open documents without prompting.
Status: Microsoft confirmed, updates available.
Council Site Actions: The affected software and/or configuration are not in production or widespread use, or are not officially supported at any of the council sites. They reported that no action was necessary.
This list is compiled by Qualys ( www.qualys.com ) as part of that company's ongoing effort to ensure its vulnerability management web service tests for all known vulnerabilities that can be scanned. As of this week Qualys scans for 5340 unique vulnerabilities. For this special SANS community listing, Qualys also includes vulnerabilities that cannot be scanned remotely.
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