In spring security versions prior to 5.4.11+, 5.5.7+ , 5.6.4+ and older unsupported versions, RegexRequestMatcher can easily be misconfigured to be bypassed on some servlet containers. Applications using RegexRequestMatcher with `.` in the regular expression are possibly vulnerable to an authorization bypass.

Spring Security versions 5.3.x prior to 5.3.2, 5.2.x prior to 5.2.4, 5.1.x prior to 5.1.10, 5.0.x prior to 5.0.16 and 4.2.x prior to 4.2.16 use a fixed null initialization vector with CBC Mode in the implementation of the queryable text encryptor. A malicious user with access to the data that has been encrypted using such an encryptor may be able to derive the unencrypted values using a dictionary attack.