A cleverly devised username might bypass LDAP authentication checks. In LDAP-authenticated Derby installations, this could let an attacker fill up the disk by creating junk Derby databases. In LDAP-authenticated Derby installations, this could also allow the attacker to execute malware which was visible to and executable by the account which booted the Derby server. In LDAP-protected databases which weren't also protected by SQL GRANT/REVOKE authorization, this vulnerability could also let an attacker view and corrupt sensitive data and run sensitive database functions and procedures. Mitigation: Users should upgrade to Java 21 and Derby 10.17.1.0. Alternatively, users who wish to remain on older Java versions should build their own Derby distribution from one of the release families to which the fix was backported: 10.16, 10.15, and 10.14. Those are the releases which correspond, respectively, with Java LTS versions 17, 11, and 8.

In Apache Derby 10.3.1.4 to 10.14.1.0, a specially-crafted network packet can be used to request the Derby Network Server to boot a database whose location and contents are under the user's control. If the Derby Network Server is not running with a Java Security Manager policy file, the attack is successful. If the server is using a policy file, the policy file must permit the database location to be read for the attack to work. The default Derby Network Server policy file distributed with the affected releases includes a permissive policy as the default Network Server policy, which allows the attack to work.

In Apache Derby 10.1.2.1, 10.2.2.0, 10.3.1.4, and 10.4.1.3, Export processing may allow an attacker to overwrite an existing file.

The password hash generation algorithm in the BUILTIN authentication functionality for Apache Derby before 10.6.1.0 performs a transformation that reduces the size of the set of inputs to SHA-1, which produces a small search space that makes it easier for local and possibly remote attackers to crack passwords by generating hash collisions, related to password substitution.