Posted by Daniel Owens via Fulldisclosure on Nov 01 Description The Apache Struts2 Core 7.4.0 and below performs session token comparisons cryptographically insecure early-exit comparison functions (e.g., `!=`, `memcmp`, byte-by-byte loops with `break`) that return as soon as the first mismatched byte is encountered. The execution time of the comparison is therefore proportional to the number of leading bytes that match, creating a measurable timing side-channel. Importantly, this...