A flaw was found in polkit. When processing input that begins with a null byte, an arithmetic error in the authentication agent helper causes an integer underflow during buffer length calculation, resulting in an out-of-bounds memory read. An attacker capable of supplying crafted input can trigger this flaw, potentially causing an application crash and resulting in a Denial of Service (DoS).
Mitigation for this issue is either not available or the currently available options do not meet the criteria for a mitigation as defined by the Red Hat Product Security team. This flaw remains subject to future review as new information becomes available. Exposure is limited: the defect is reachable only by a local/adjacent low-privileged user interacting with the polkit authentication agent and results at most in a crash (availability) of the affected process.