REDHAT-BUG-2449006: High severity Libarchive libarchive vulnerability

A Heap Out-of-Bounds Read vulnerability exists in the RAR archive processing logic of the libarchive library. The issue arises from improper validation of the LZSS sliding window size after transitions between compression methods (PPMd and LZSS). Due to a mismatch between the allocated buffer size and the expected dictionary size, the copyfromlzsswindow() function performs out-of-bounds memory reads. This allows a specially crafted RAR archive to leak heap memory through the archivereaddata() API before integrity checks (CRC) are enforced. The vulnerability can be exploited remotely without authentication or user interaction in systems that automatically process archives, leading to disclosure of sensitive information.