What is the CVSS score of CVE-2025-54574?

CVE-2025-54574 has a CVSS 3.1 base score of 9.3 (Critical). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:H. EPSS exploitation probability: 3.0%.

Which versions of Squid are affected by CVE-2025-54574?

Organizations using Squid face critical risk from CVE-2025-54574, a heap-based buffer overflow vulnerability rated CVSS 9.3.. A patch is available.

How to fix or mitigate CVE-2025-54574?

Within 7 days: Identify all affected systems and apply vendor patches promptly. If patching is delayed, consider network segmentation to limit exposure.

Squid CVE-2025-54574

CRITICAL

Heap-based Buffer Overflow (CWE-122)

2025-08-01 security-advisories@github.com

RCE Buffer Overflow Heap Overflow Red Hat Suse Squid

9.3

CVSS 3.1

CVSS VectorNVD

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:H

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Changed

Confidentiality

None

Integrity

Low

Availability

High

Lifecycle Timeline

Analysis Generated

Mar 28, 2026 - 19:04 vuln.today

Patch released

Mar 28, 2026 - 19:04 nvd

Patch available

CVE Published

Aug 01, 2025 - 18:15 nvd

CRITICAL 9.3

DescriptionNVD

Squid is a caching proxy for the Web. In versions 6.3 and below, Squid is vulnerable to a heap buffer overflow and possible remote code execution attack when processing URN due to incorrect buffer management. This has been fixed in version 6.4. To work around this issue, disable URN access permissions.

AnalysisAI

Squid is a caching proxy for the Web. Rated critical severity (CVSS 9.3), this vulnerability is remotely exploitable, no authentication required, low attack complexity.

Technical ContextAI

This vulnerability is classified under CWE-122. Squid is a caching proxy for the Web. In versions 6.3 and below, Squid is vulnerable to a heap buffer overflow and possible remote code execution attack when processing URN due to incorrect buffer management. This has been fixed in version 6.4. To work around this issue, disable URN access permissions. Affected products include: Squid-Cache Squid. Version information: version 6.4..

RemediationAI

A vendor patch is available. Apply the latest security update as soon as possible. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.