Moderate Vulnerability in libxml2: Denial of Service via Crafted XML Input
Summary
ALSA-2026:69655: Moderate: libxml2 security, bug fix, and enhancement update. Affects libxml2 versions < 2.9.7-21.el8_10.8. Fixed in 2.9.7-21.el8_10.8. 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 development toolbox that implements various XML standards, providing essential functionalities for XML parsing and manipulation. It is integral to many applications that rely on XML data processing. However, vulnerabilities in libxml2 can lead to severe security risks, including denial of service attacks, which can disrupt application availability and integrity.
Vulnerability Detail
The vulnerability identified in libxml2 is a denial of service (DoS) issue caused by a use-after-free error when processing crafted XML input. This flaw, documented as CVE-2026-6653, allows an attacker to exploit the library by sending specially crafted XML data, potentially leading to application crashes and service interruptions. The issue arises from improper memory management within the library, which can be triggered by malicious input.
How To Fix
Minimum fixed version
2.9.7-21.el8_10.8
This is the first release that contains the fix.
sudo dnf update libxml2Tip — Not sure which version your app runs? Vulert can match this fix to it. Scan free →
Workaround
Currently, there are no specific workarounds recommended for this vulnerability. The best course of action is to apply the available patch by updating the affected packages.
Conclusion
The libxml2 library has a moderate vulnerability that can lead to denial of service through crafted XML input. It is crucial for users to update their packages to the patched version to mitigate risks. Regular monitoring for vulnerabilities using tools like Vulert can help maintain application security.
See every vulnerability recorded for libxml2 →
FAQ
CVE-2026-6653 is a vulnerability in the libxml2 library that can lead to denial of service due to a use-after-free error when handling crafted XML input.
You can use Vulert, which monitors open-source vulnerabilities in your software. By utilizing the Vulert playground, you can check if your application is affected by this vulnerability without needing to sign up.
The primary impact of this vulnerability is the potential for denial of service, which can cause applications to crash and become unavailable to users.
While the primary concern is service disruption, depending on the application, there may be risks of data loss if the application crashes unexpectedly during critical operations.
If immediate updates are not possible, consider isolating the application from untrusted input and monitoring its behavior closely until the patch can be applied.
Related vulnerabilities
Recent vulnerabilities recorded for libxml2.
