Critical Out-of-Bounds Read Vulnerability in libxml2
Summary
ALPINE-CVE-2021-3517: There is a flaw in the xml entity encoding functionality of libxml2 in versions before 2.9.11. Affects libxml2 versions < 2.9.9-r5. Fixed in 2.9.9-r5. How to fix ↓
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Background
libxml2 is a widely-used XML parsing library that provides a range of functionalities for processing XML documents. It is known for its performance and compliance with standards, making it a popular choice for applications that require XML manipulation. However, certain versions of libxml2 are vulnerable to a flaw in its entity encoding functionality, which can lead to security issues if exploited.
Vulnerability Detail
The vulnerability identified as CVE-2021-3517 arises from a flaw in the xml entity encoding functionality of libxml2 versions prior to 2.9.11. An attacker can exploit this vulnerability by supplying a crafted file to an application linked with the affected version of libxml2, potentially triggering an out-of-bounds read. This can lead to application crashes, and in some cases, may expose sensitive memory information, impacting confidentiality and integrity.
How To Fix
Minimum fixed version
2.9.9-r5
This is the first release that contains the fix.
sudo apk add --upgrade libxml2Tip — Not sure which version your app runs? Vulert can match this fix to it. Scan free →
Workaround
As a temporary workaround, avoid processing untrusted XML files with applications that utilize vulnerable versions of libxml2. Implement strict validation and sanitization of input files to mitigate the risk of exploitation.
Conclusion
The vulnerability CVE-2021-3517 in libxml2 poses significant risks to applications that rely on this library for XML processing. It is crucial to update to the latest patched version to mitigate these risks and ensure application security.
See every vulnerability recorded for libxml2 →
FAQ
CVE-2021-3517 is a vulnerability in libxml2 that allows for out-of-bounds reads due to a flaw in its entity encoding functionality.
Versions of libxml2 prior to 2.9.11 are affected by this vulnerability.
The vulnerability can lead to application crashes and may expose sensitive information, affecting confidentiality and integrity.
You can use Vulert, which monitors and alerts for open-source vulnerabilities in real-time. Visit Vulert Scanner to check your application without needing to sign up.
The CVSS score for CVE-2021-3517 is 8.6, indicating a high severity level.
References
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