A configuration injection flaw was found in Haproxy. The loose regular expression allows for using special characters that can change the configuration's directive in uncontrolled ways. All changes are limited to the same line. An attacker could leverage this injection to leak limited amounts of information from the environment, Haproxy's internal variables like the current TLS session keys and random, brute force contents in files, and forcefully prevent new changes to the Haproxy generated configuration by breaking it.