Heap Buffer Overflow Vulnerability in Squid Package - CVE-2025-54574
Summary
CVE-2025-54574: Squid is a caching proxy for the Web. Affects squid across 2 version ranges.
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No fix is published. How to fix ↓
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Background
Squid is a widely used caching proxy for the Web, designed to improve web performance by caching frequently accessed content. It supports various protocols and is known for its flexibility and scalability. However, certain versions of Squid have been found to be vulnerable to a serious security issue that could allow attackers to exploit the system.
Vulnerability Detail
The vulnerability identified as CVE-2025-54574 affects Squid versions 6.3 and below, where a heap buffer overflow occurs due to improper buffer management when processing URN. This flaw can potentially lead to remote code execution, allowing attackers to execute arbitrary code on the affected system, posing significant security risks.
How To Fix
No fixed version is published for this vulnerability.
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Workaround
As a temporary workaround, you can disable URN access permissions to mitigate the risk of exploitation. This can be done by modifying the Squid configuration file (usually located at /etc/squid/squid.conf) and adding the following line: 'urn_access deny all'. After making changes, restart the Squid service using
sudo systemctl restart squid'.
Conclusion
CVE-2025-54574 represents a critical vulnerability in the Squid caching proxy, necessitating prompt action to update to the patched version or implement workarounds to mitigate risks. Regular monitoring and updates are essential to maintain security.
See every vulnerability recorded for squid →
FAQ
CVE-2025-54574 is a vulnerability in the Squid caching proxy that allows for a heap buffer overflow, potentially leading to remote code execution.
Versions 6.3 and below of Squid are affected by this vulnerability.
You can use Vulert, which monitors open-source vulnerabilities in your software using a manifest file like package-lock.json. Visit Vulert Scanner to check if your application is affected without any signup.
If immediate updates are not possible, you should disable URN access permissions as a temporary workaround to reduce the risk of exploitation.
More information can be found in the official CVE database or through security advisories related to Squid.
References
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