Published: 11 July 2019

An issue was discovered in Squid 2.x through 2.7.STABLE9, 3.x through 3.5.28, and 4.x through 4.7. When Squid is configured to use Basic Authentication, the Proxy-Authorization header is parsed via uudecode. uudecode determines how many bytes will be decoded by iterating over the input and checking its table. The length is then used to start decoding the string. There are no checks to ensure that the length it calculates isn't greater than the input buffer. This leads to adjacent memory being decoded as well. An attacker would not be able to retrieve the decoded data unless the Squid maintainer had configured the display of usernames on error pages.



CVSS 3 base score: 5.9


Package Release Status
Launchpad, Ubuntu, Debian
Released (4.8)
Ubuntu 18.04 LTS (Bionic Beaver) Does not exist

Ubuntu 16.04 ESM (Xenial Xerus) Does not exist

Ubuntu 14.04 ESM (Trusty Tahr) Does not exist

Upstream: (v4)
Launchpad, Ubuntu, Debian
Upstream Needed

Ubuntu 18.04 LTS (Bionic Beaver)
Released (3.5.27-1ubuntu1.3)
Ubuntu 16.04 ESM (Xenial Xerus)
Released (3.5.12-1ubuntu7.8)
Ubuntu 14.04 ESM (Trusty Tahr) Does not exist