The issue results from the lack of proper validation of user-supplied data, which can result in a read past the end of an allocated buffer. An attacker can leverage this in conjunction with other vulnerabilities to execute code in the context of the "nobody" user.
Created squid tracking bugs for this issue: Affects: fedora-all [bug 1934559]
External References: https://www.zerodayinitiative.com/advisories/ZDI-21-157/
*** This bug has been marked as a duplicate of bug 1939939 ***