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 protocol data.
Does this matter?
EPSS puts the probability of exploitation in the next 30 days at 12.9%, higher than 96% of all known CVEs. Patch or mitigate before the next change window.
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.
- CVSS 3.1
- 5.3 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
- EPSS
- 12.95% probability · 96th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-125
- Affected
- squid-cache/squid · fedoraproject/fedora · debian/debian linux
- Source
- cve@mitre.org
EPSS 12.9% since 3 November 2026; no change recorded yet. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- http://www.openwall.com/lists/oss-security/2021/10/04/1Mailing List, Third Party Advisory
- http://www.squid-cache.org/Versions/Product, Vendor Advisory
- https://github.com/squid-cache/squid/security/advisories/GHSA-rgf3-9v3p-qp82Broken Link
- 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/
- https://security.gentoo.org/glsa/202105-14Third Party Advisory
- https://www.debian.org/security/2022/dsa-5171Third Party Advisory
- https://www.zerodayinitiative.com/advisories/ZDI-21-157/Third Party Advisory, VDB Entry
- http://www.openwall.com/lists/oss-security/2021/10/04/1Mailing List, Third Party Advisory
- http://www.squid-cache.org/Versions/Product, Vendor Advisory
- https://github.com/squid-cache/squid/security/advisories/GHSA-rgf3-9v3p-qp82Broken Link
- 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/
- https://security.gentoo.org/glsa/202105-14Third Party Advisory
- https://www.debian.org/security/2022/dsa-5171Third Party Advisory
- https://www.zerodayinitiative.com/advisories/ZDI-21-157/Third Party Advisory, VDB Entry
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.