CVE-2026-55206 | BDVDB-2026-346247 Detail

Description#

py7zr is a Python-based library and utility to support 7zip archive compression, decompression, encryption and decryption. Prior to 1.1.3, PackInfo._read() in archiveinfo.py used an O(n^2) cumulative sum pattern for attacker-controlled numstreams values parsed from archive headers, allowing a crafted .7z archive to cause excessive CPU consumption during SevenZipFile.init() before extraction. This issue is fixed in version 1.1.3.

Impact#

Weaknesses#

References#

Exploit#

History#

1. Version 12026-07-08Record published in the CVE List.
2. Version 22026-07-09Most recent update recorded in the CVE List.