QID 356430

due to a buffer overflow bug squid is vulnerable to a denial of service attack against http digest authentication an issue was discovered in squid through 4.7.
When handling requests from users, squid checks its rules to see if the request should be denied.
Squid by default comes with rules to block access to the cache manager, which serves detailed server information meant for the maintainer.
This rule is implemented via url_regex.
The handler for url_regex rules url decodes an incoming request.
This allows an attacker to encode their url to bypass the url_regex check, and gain access to the blocked resource. (
( CVE-2019-12524) 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 isnt 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. (
( CVE-2019-12529) an issue was discovered in squid 3.x and 4.x through 4.8 when the append_domain setting is used (because the appended characters do not properly interact with hostname length restrictions).
Due to incorrect message processing, it can inappropriately redirect traffic to origins it should not be delivered to. (
There are no effects on squid itself, nor on any upstream servers.

Successful exploitation of this vulnerability could lead to a securitybreach or could affect integrity, availability, and confidentiality.