An Infinite Loop Denial-of-Service vulnerability exists in the RAR5 decompression implementation of libarchive. The flaw occurs in the uncompress_file() routine within archive_read_support_format_rar5.c due to a logical deadlock between the filter activation threshold and the half-window output limiter. When a specially crafted RAR5 archive is processed through archive_read_data(), the decompressor enters a state where neither the filter activation condition nor the output window progress condition can be satisfied. As a result, the loop continues indefinitely while consuming 100% CPU. Because the archive passes all CRC and checksum validation, the issue can be triggered using a valid-looking archive without authentication or user interaction. This allows attackers to exhaust worker threads or processing pipelines in applications that automatically extract or scan archives.