CVE-2025-54574

A heap-based buffer overflow flaw was found in the Squid caching proxy. When processing the Uniform Resource Name (URNs), specific conditions can lead to remote code execution.

This vulnerability is Important because the heap-based buffer overflow occurs during URN processing in Squid’s core request-handling path, which is exposed to untrusted, remote input. Unlike flaws that merely cause a service crash, this defect allows an attacker to manipulate heap memory structures, potentially achieving arbitrary code execution within the Squid process context. Since Squid often runs with elevated privileges and serves as a gateway between internal and external networks, successful exploitation could provide a remote attacker with direct control over the proxy server, enabling them to pivot into internal systems, intercept sensitive traffic, or alter cached content.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Users can disable URN access permissions to mitigate this issue.