CVE-2023-46724

Squid is a caching proxy for the Web. Due to an Improper Validation of Specified Index bug, Squid versions 3.3.0.1 through 5.9 and 6.0 prior to 6.4 compiled using --with-openssl are vulnerable to a Denial of Service attack against SSL Certificate validation. This problem allows a remote server to perform Denial of Service against Squid Proxy by initiating a TLS Handshake with a specially crafted SSL Certificate in a server certificate chain. This attack is limited to HTTPS and SSL-Bump. This bug is fixed in Squid version 6.4. In addition, patches addressing this problem for the stable releases can be found in Squids patch archives. Those who you use a prepackaged version of Squid should refer to the package vendor for availability information on updated packages.

Weakness

The product does not validate, or incorrectly validates, a certificate.

Affected Software

Potential Mitigations

Related Attack Patterns

• https://cwe.mitre.org/data/definitions/459.html
• https://cwe.mitre.org/data/definitions/475.html

References

• http://www.squid-cache.org/Versions/v5/SQUID-2023_4.patch
• http://www.squid-cache.org/Versions/v6/SQUID-2023_4.patch
• https://github.com/squid-cache/squid/commit/b70f864940225dfe69f9f653f948e787f99c3810
• https://github.com/squid-cache/squid/security/advisories/GHSA-73m6-jm96-c6r3
• https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/A5QASTMCUSUEW3UOMKHZJB3FTONWSRXS/
• https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/MEV66D3PAAY6K7TWDT3WZBLCPLASFJDC/
• https://security.netapp.com/advisory/ntap-20231208-0001/