Critical Security Update for libXfont2: Addressing Out-Of-Bounds Read/Write and Privilege Escalation Vulnerabilities
Summary
ALSA-2026:55448: Important: libXfont2 security update. Affects libXfont2 versions < 2.0.6-5.el10_2.3. Fixed in 2.0.6-5.el10_2.3. How to fix ↓
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Background
libXfont2 is a runtime library used in the X.Org X11 system, which provides essential font handling capabilities for graphical applications. It is a crucial component for rendering text in various applications that rely on the X Window System. The library's functionality includes managing font files and facilitating communication between font servers and clients. However, vulnerabilities in this library can lead to severe security risks, including unauthorized access and system compromise.
Vulnerability Detail
The vulnerabilities identified in libXfont2 include an Out-Of-Bounds Read/Write issue and a Privilege Escalation vulnerability due to a Heap Buffer Overflow in the Font Server Client. The Out-Of-Bounds Read/Write (CVE-2026-59679) can allow attackers to read or write memory locations beyond the allocated buffer, potentially leading to data corruption or arbitrary code execution. The Privilege Escalation vulnerability (CVE-2026-44950) can enable attackers to gain elevated privileges, allowing them to execute malicious actions with higher system rights, which poses a significant risk to system integrity and security.
How To Fix
Minimum fixed version
2.0.6-5.el10_2.3
This is the first release that contains the fix.
sudo dnf update libXfont2Tip — Not sure which version your app runs? Vulert can match this fix to it. Scan free →
Workaround
As a temporary measure, users can limit access to the affected library or disable the font server functionality until the update is applied. However, this may impact applications relying on font rendering.
Conclusion
The vulnerabilities in libXfont2 pose significant risks to system security, including potential privilege escalation and memory corruption. It is crucial for users to update their packages to the latest patched versions to mitigate these risks. Utilizing tools like Vulert can help monitor and identify vulnerabilities in your applications effectively.
See every vulnerability recorded for libXfont2 →
FAQ
The main vulnerabilities include an Out-Of-Bounds Read/Write and a Privilege Escalation vulnerability due to a Heap Buffer Overflow.
You can use Vulert, which monitors and alerts for open-source vulnerabilities in your software using a manifest file. Visit Vulert Scanner to check if your application is affected without any signup.
These vulnerabilities can lead to unauthorized access, data corruption, and privilege escalation, allowing attackers to execute malicious actions with elevated rights.
Yes, a patch is available. Users should update to version 2.0.6-5.el10_2.3 or later of the libXfont2 and libXfont2-devel packages.
As a temporary workaround, limit access to the affected library or disable the font server functionality until you can apply the update.
Related vulnerabilities
Recent vulnerabilities recorded for libXfont2.
