VULNERABILITY INTELLIGENCE
CVE-2026-55206
EPSS probability0.27%
CISA KEVNot currently listed
Published2026-07-08
Last modified2026-10-25
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.
Weakness classification
- security-advisories@github.com: CWE-407