Spring Framework DoS via conditional HTTP request

Description

Applications that parse ETags from If-Match or If-None-Match request headers are vulnerable to DoS attack.

Affected Spring Products and Versions

org.springframework:spring-web in versions

6.1.0 through 6.1.11
6.0.0 through 6.0.22
5.3.0 through 5.3.37

Older, unsupported versions are also affected

Mitigation

Users of affected versions should upgrade to the corresponding fixed version.
6.1.x -> 6.1.12
6.0.x -> 6.0.23
5.3.x -> 5.3.38
No other mitigation steps are necessary.

Users of older, unsupported versions could enforce a size limit on If-Match and If-None-Match headers, e.g. through a Filter.