haproxy: Mishandling of priority flag in short HEADERS frame by HTTP/2 decoder allows for crash

A flaw was found in HAProxy, versions before 1.8.17 and 1.9.1. Mishandling occurs when a priority flag is set on too short HEADERS frame in the HTTP/2 decoder, allowing an out-of-bounds read and a subsequent crash to occur. A remote attacker can exploit this flaw to cause a denial of service. Tho...