Integer Overflow in libxml2 Buffer Handling Functions
Summary
CVE-2022-29824: In libxml2 before 2.9.14, several buffer handling functions in buf.c (xmlBuf*) and tree.c (xmlBuffer*) don't check for integer overflows. Affects libxml2 across 4 version ranges.
< 2.9.14-r0
< 6c283d83eccd940bcde15634ac8c7f100e3caefd
< 2554a2408e09f13652049e5ffb0d26196b02ebab
< 7846b0a677f8d3ce72486125fa281e92ac9970e8
Fixed in 2.9.14-r0. How to fix ↓
Check if this vulnerability affects your application
Upload a manifest or SBOM and we'll show whether you're affected, plus every other risky package in the same scan.
No signup required · Results in about 60 seconds
Background
libxml2 is a widely used open-source library for parsing and manipulating XML files. It provides various functions for buffer handling, including xmlBuf* and xmlBuffer*. These functions are used by other software, such as libxslt, to process XML data. However, prior to version 2.9.14, libxml2's buffer handling functions did not properly check for integer overflows, which could lead to out-of-bounds memory writes.
Vulnerability Detail
The vulnerability, identified as CVE-2022-29824, arises due to the lack of integer overflow checks in libxml2's buffer handling functions. An attacker can exploit this vulnerability by crafting a multi-gigabyte XML file and tricking a victim into opening it. When the victim opens the malicious XML file, it triggers the integer overflow, resulting in out-of-bounds memory writes. This can potentially lead to remote code execution or denial of service attacks. The vulnerability also affects other software that utilizes libxml2's buffer functions, including libxslt.
How To Fix
Minimum fixed version
2.9.14-r0
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 workaround, users can avoid opening untrusted or excessively large XML files until the libxml2 library is updated to a fixed version. Additionally, it is advisable to keep software and libraries up to date to mitigate potential security risks.
Conclusion
In conclusion, the integer overflow vulnerability in libxml2's buffer handling functions can lead to out-of-bounds memory writes and potential remote code execution or denial of service attacks. It is crucial to update libxml2 to version 2.9.14 or later to mitigate this vulnerability. Regularly updating software and libraries is essential for maintaining a secure environment. For further support on vulnerability remediation, you can contact DevNack.com.
See every vulnerability recorded for libxml2 →
FAQ
libxml2 is an open-source library for parsing and manipulating XML files. It is widely used in various software applications and provides functions for XML processing.
The vulnerability allows an attacker to trigger out-of-bounds memory writes, which can lead to remote code execution or denial of service attacks. It requires the victim to open a crafted, multi-gigabyte XML file.
Versions of libxml2 prior to 2.9.14 are affected by this vulnerability.
Yes, libxslt is also affected by this vulnerability as it utilizes libxml2's buffer functions.
To fix this vulnerability, you should update the libxml2 library to version 2.9.14 or later. Ensure that you are using the latest available version from the official repository or package manager.
References
Related vulnerabilities
Recent vulnerabilities recorded for libxml2.
