Home/CVE/An issue was discovered in Squid 5.0.6 through 5.1.x before 5.2. When validating an origin server or peer certificate, S
CVE

CVE-2021-41611

An issue was discovered in Squid 5.0.6 through 5.1.x before 5.2. When validating an origin server or peer certificate, S

An issue was discovered in Squid 5.0.6 through 5.1.x before 5.2. When validating an origin server or peer certificate, Squid may incorrectly classify certain certificates as trusted. This problem allows a remote server to obtain security trust well improperly.

This indication of trust may be passed along to clients, allowing access to unsafe or hijacked services.

HIGH · CVSS 7.5 EPSS 0.0112
Schedule remediation
  • CVSS base score ≥ 7.0
Sigma rules0 YARA rules0
⬡

Weakness Classification

CWE-295Improper Certificate Validation
▤

Affected Products & Versions

2
squid-cache squid>= 5.0.6 and < 5.2
fedoraproject fedoraall versions
▣

Scoring & Timeline

7.5
HIGH · CVSS v3.1 · cve@mitre.org
View on NVD
Attack Vector
Network Adjacent Local Physical
Attack Complexity
Low High
Privileges Required
None Low High
User Interaction
None Required
Scope
Unchanged Changed
Confidentiality
None Low High
Integrity
None Low High
Availability
None Low High
Published to NVD18 Oct 2021 · 09:15 AM
CVSS VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
🔗

References & Sources

4
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
http://www.openwall.com/lists/oss-security/2021/12/23/2Mailing ListThird Party Advisory
http://www.squid-cache.org/Versions/v6/changesets/squid-6-43d6b5c81b88ec2256b430c69a872a1e4f324e4a.patchVendor Advisory
https://github.com/squid-cache/squid/security/advisories/GHSA-47m4-g3mv-9q5rPatchThird Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CWQ2WKDWTSO47S3F6XJJ6HGG2ULWEAE4/
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