CVE-2024-23638mediumCWE-825

CVE-2024-23638: medium-severity vulnerability in squid-cache squid

SQUID-2023:11 Denial of Service in Cache Manager

Published · Updated

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25Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 6.5epss 60%
What the vendors declare (VEX)

Official vendor statements in CSAF/VEX format: whether their product is affected, already fixed, or ruled out — and why. These are the vendor's assertions, not Vexday's judgment.

Red HatVEX document ↗
Affected
2 products (8 components)
Red Hat Enterprise Linux 6 · Red Hat Enterprise Linux 7
workaround: Restrict entry to Cache Manager through Squid's primary access control: http_access deny manager
Fixed
2 products (43 components)
Red Hat Enterprise Linux AppStream (v. 8) · Red Hat Enterprise Linux AppStream (v. 9)
fix ↗
In short

Squid versions before 6.6 have a memory bug that crashes the Cache Manager when generating error pages. A trusted user can trigger this to cause denial of service by requesting specific reports.

Technical detail

An expired pointer reference in Squid's Cache Manager causes a use-after-free condition when generating error responses. A trusted client can trigger this via malformed or specific Cache Manager requests, leading to process crash and service unavailability.

Summary generated and translated by AI from the official description.
Squid is a caching proxy for the Web. Due to an expired pointer reference bug, Squid prior to version 6.6 is vulnerable to a Denial of Service attack against Cache Manager error responses. This problem allows a trusted client to perform Denial of Service when generating error pages for Client Manager reports. Squid older than 5.0.5 have not been tested and should be assumed to be vulnerable. All Squid-5.x up to and including 5.9 are vulnerable. All Squid-6.x up to and including 6.5 are vulnerable. This bug is fixed by Squid version 6.6. In addition, patches addressing this problem for the stable releases can be found in Squid's patch archives. As a workaround, prevent access to Cache Manager using Squid's main access control: `http_access deny manager`.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Affected products
squid-cache · squid
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