{"schemaVersion":3,"id":"CVE-2026-77640","aliases":["UBUNTU-CVE-2026-77640","DEBIAN-CVE-2026-77640"],"status":"published","duplicateOf":null,"title":null,"description":"tor before 0.4.9.9 was prone to an infinite loop when decompressing a truncated zlib/gzip  stream with done=1. A truncated stream never reaches Z_STREAM_END,  causing zlib to return Z_BUF_ERROR with no input remaining, which  buf_add_compress() mistook for a full output buffer and retried forever. Fixed by returning TOR_COMPRESS_ERROR in that case so the caller can abort cleanly. 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