Improper Certificate Validation in Squid - CVE-2021-41611
Published: October 4, 2021
Vulnerability identifier: #VU57025
CSH Severity: Medium
CVSS v4: 5.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2021-41611
CWE-ID: CWE-295
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to perform a MitM attack.
The vulnerability exists due to improper certificate validation when the TLS server certificate is signed by multiple CAs. A remote attacker can perform a mand-in-the-middle attack against proxy server users.
Affected software
Squid
Fedora
squid
Fedora
squid
How to mitigate CVE-2021-41611
Install updates from vendor's website.
Squid - update to 5.2
squid - addressed in versions 5.2-1.fc33, 5.2-1.fc34, 5.2-1.fc35
squid - addressed in versions 5.2-1.fc33, 5.2-1.fc34, 5.2-1.fc35