In Apache HTTP Server versions 2.4.0 to 2.4.23, mod_session_crypto was encrypting its data/cookie using the configured ciphers with possibly

Summary

In Apache HTTP Server versions 2.4.0 to 2.4.23, mod_session_crypto was encrypting its data/cookie using the configured ciphers with possibly either CBC or ECB modes of operation (AES256-CBC by default), hence no selectable or builtin authenticated encryption. This made it vulnerable to padding oracle attacks, particularly with CBC.

Timeline

1. Dec 23, 2016Public exploit on Exploit-DB

   EDB-40961

2. Jul 27, 2017, 9:00 PM UTCCVE published
3. Sep 16, 2024, 5:52 PM UTCRecord last updated
4. Oct 28, 2026EPSS reached 10%

   FIRST estimates at least a 10% chance of exploitation in the next 30 days

Affected versions

• Apache Software Foundation Apache HTTP Server

  2.4.0 to 2.4.23

References 26