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Vulnerability record · CVE-2024-45802 · published 28 October 2024

CVE-2024-45802: Squid proxy input validation and resource lifetime bugs allow DoS

Squid Cache · Squid

Squid, the open source caching proxy, mishandles input validation and resource lifetime in ways that let a trusted upstream server cause a denial of service against all clients using the proxy. The flaw is fixed in the default build configuration of Squid 6.10, so unpatched proxies remain exposed.

7.5 CVSS 3.1 High EPSS 48% · top 1.2% CWE-20 · Improper input validation
7.5CVSS 3.1 base score
48%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
3References
17 Jun 2026Last modified by NVD

Description

Squid is an open source caching proxy for the Web supporting HTTP, HTTPS, FTP, and more. Due to Input Validation, Premature Release of Resource During Expected Lifetime, and Missing Release of Resource after Effective Lifetime bugs, Squid is vulnerable to Denial of Service attacks by a trusted server against all clients using the proxy. This bug is fixed in the default build configuration of Squid version 6.10.

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

Automated analysis

Generated by VULONE's analysis model from the NVD record, CISA KEV and EPSS data on 20 September 2026. Confidence: medium.

high priorityNetwork-reachable denial of service with no authentication or interaction required and a high EPSS score, though impact is limited to availability and a fix exists.

What it is

Squid, the open source caching proxy, mishandles input validation and resource lifetime in ways that let a trusted upstream server cause a denial of service against all clients using the proxy. The flaw is fixed in the default build configuration of Squid 6.10, so unpatched proxies remain exposed.

Impact

An attacker controlling a trusted server can degrade or halt proxy service for every client relying on it, disrupting web access rather than gaining code execution or data access.

Attack surface

Reachable over the network (AV:N) with no privileges (PR:N) and no user interaction (UI:N); the malicious party is a trusted server the proxy communicates with, not an anonymous internet client.

Exploitation

Not listed in CISA KEV and no public exploit references are tagged in the record, but EPSS is high at 0.479 (98.8th percentile), indicating elevated predicted exploitation likelihood.

What to do

  • Upgrade Squid to version 6.10 or later, which fixes the bug in the default build configuration.
  • If immediate upgrade is not possible, apply the vendor mitigation guidance in advisory GHSA-f975-v7qw-q7hj.
  • Track downstream vendor advisories (Debian LTS, NetApp) for backported packages covering your deployment.
  • Limit which upstream servers the proxy is allowed to contact and monitor trusted-server traffic for abnormal resource consumption.

Detection

  • Monitor Squid process memory and file descriptor usage for abnormal growth or exhaustion.
  • Alert on proxy availability drops, worker restarts, or client connection failures clustered around specific upstream servers.
  • Review Squid cache and error logs for repeated failures tied to a single trusted origin server.

This assessment is produced automatically and is not human-reviewed. Verify against the vendor advisory before acting on it.

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://github.com/squid-cache/squid/security/advisories/GHSA-f975-v7qw-q7hj MitigationThird Party Advisory
https://lists.debian.org/debian-lts-announce/2025/03/msg00009.html
https://security.netapp.com/advisory/ntap-20250103-0004/

Track CVE-2024-45802 inside VULONE

Watch it alongside the ransomware crews, C2 infrastructure and forum chatter that reference it, query it through the API and pull it into your SIEM over TAXII.

Start free Open in platform

Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2024-45802), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.