The authentication module for Apache 2.0.40 through 2.0.45 on Unix does not properly handle threads safely when using the crypt_r or crypt functions, which allows remote attackers to cause a denial of service (failed Basic authentication with valid usernames and passwords) when a threaded MPM is used.
Exploit prediction scoring system (EPSS) score
EPSS Score 0.194
EPSS Ranking 95.1%