CVE-2011-2825 in Chrome
Summary
by MITRE
Use-after-free vulnerability in Google Chrome before 13.0.782.215 allows remote attackers to cause a denial of service or possibly have unspecified other impact via vectors involving custom fonts.
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Analysis
by VulDB Data Team • 11/18/2021
The vulnerability identified as CVE-2011-2825 represents a critical use-after-free flaw in Google Chrome browser versions prior to 13.0.782.215. This type of vulnerability occurs when a program continues to reference memory that has already been freed, creating potential exploitation opportunities for remote attackers. The specific conditions leading to this vulnerability involve the browser's handling of custom fonts, which demonstrates how font rendering systems can become attack vectors in modern web browsers. The flaw is particularly concerning because it affects the core rendering engine of the browser, potentially allowing attackers to manipulate memory operations through malicious web content.
The technical implementation of this vulnerability stems from improper memory management during font processing operations within Chrome's rendering pipeline. When the browser encounters custom fonts in web pages, it allocates memory for font data structures and subsequently frees this memory when processing is complete. However, a race condition or improper validation mechanism allows attackers to trigger the reuse of freed memory references, creating opportunities for arbitrary code execution or system instability. This use-after-free condition falls under the CWE-416 category of "Use After Free" vulnerabilities, which are classified as severe memory corruption flaws that can lead to privilege escalation and system compromise.
The operational impact of this vulnerability extends beyond simple denial of service scenarios, as indicated by the unspecified other impacts mentioned in the description. Remote attackers could potentially leverage this flaw to execute malicious code on victim systems, bypass security restrictions, or cause complete browser crashes that could be exploited for more sophisticated attacks. The attack vector involving custom fonts is particularly dangerous because web content can easily include custom font definitions through css font-face declarations, making exploitation relatively straightforward and widespread. This vulnerability aligns with ATT&CK technique T1059.007 for 'Command and Scripting Interpreter: JavaScript' and T1203 for 'Exploitation for Client Execution' as attackers could use this flaw to execute malicious scripts or payloads through compromised font rendering.
Mitigation strategies for CVE-2011-2825 primarily focus on immediate browser updates to versions 13.0.782.215 and later, which contain the necessary memory management fixes. Organizations should implement comprehensive patch management procedures to ensure all browser installations are updated promptly. Additionally, security configurations such as disabling custom font loading or implementing strict content security policies can provide additional defense-in-depth measures. Network-level protections including web application firewalls and browser security extensions can help detect and prevent exploitation attempts. The vulnerability serves as a reminder of the critical importance of proper memory management in browser engines and highlights the need for continuous security auditing of rendering systems that handle untrusted input from web content.