CVE-2011-0480 in Chrome
Summary
by MITRE
Multiple buffer overflows in vorbis_dec.c in the Vorbis decoder in FFmpeg, as used in Google Chrome before 8.0.552.237 and Chrome OS before 8.0.552.344, allow remote attackers to cause a denial of service (memory corruption and application crash) or possibly have unspecified other impact via a crafted WebM file, related to buffers for (1) the channel floor and (2) the channel residue.
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 10/12/2021
The vulnerability identified as CVE-2011-0480 represents a critical security flaw within the Vorbis decoder component of FFmpeg, which was widely utilized in Google Chrome browser versions prior to 8.0.552.237 and Chrome OS versions before 8.0.552.344. This vulnerability manifests through multiple buffer overflows that occur in the vorbis_dec.c source file, specifically targeting the channel floor and channel residue buffer handling mechanisms. The flaw exists at the intersection of multimedia processing and memory management, creating a pathway for malicious actors to exploit the decoding process through crafted WebM media files.
The technical implementation of this vulnerability stems from insufficient bounds checking within the Vorbis audio decoder's buffer allocation and data handling routines. When processing specially crafted WebM files, the decoder fails to properly validate the size and structure of channel floor and channel residue data segments, leading to memory corruption that can result in application crashes or potentially more severe consequences. This type of vulnerability falls under CWE-121, which specifically addresses stack-based buffer overflow conditions, and aligns with ATT&CK technique T1203, which covers exploitation of input validation vulnerabilities through malformed media files. The buffer overflow conditions occur during the decoding process when the application attempts to write data beyond the allocated memory boundaries for these specific audio channel components.
The operational impact of CVE-2011-0480 extends beyond simple denial of service scenarios, as the memory corruption can potentially be leveraged for more sophisticated attacks. Remote attackers can craft WebM files that trigger these buffer overflows, causing Chrome browsers to crash or become unstable, thereby disrupting user experience and potentially creating opportunities for further exploitation. The vulnerability's presence in widely deployed browser versions made it particularly dangerous, as it could be exploited through standard web browsing activities without requiring any special privileges or user interaction beyond visiting a malicious website. This makes the vulnerability particularly concerning from a threat actor perspective, as it represents a low-effort attack vector with potentially high impact.
Mitigation strategies for this vulnerability primarily focus on immediate software updates and patches to address the underlying buffer overflow conditions in the Vorbis decoder. System administrators and users should prioritize updating to Chrome versions 8.0.552.237 or later, and Chrome OS versions 8.0.552.344 or later, which contain the necessary fixes for the buffer overflow issues. Additionally, implementing network-level controls such as content filtering and sandboxing mechanisms can provide additional protection layers against exploitation attempts. The vulnerability's classification under CWE-121 and its potential for memory corruption highlights the importance of proper input validation and bounds checking in multimedia processing libraries, serving as a reminder of the critical need for robust memory management practices in security-sensitive applications. Organizations should also consider implementing automated patch management systems to ensure timely deployment of security updates and reduce the window of vulnerability exposure.