CVE-2026-55206

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.

CVSS

No CVSS.

References

Link	Resource
https://github.com/miurahr/py7zr/commit/d7aa3a197d15c75a65b24f796d3a69f83806d3f8
https://github.com/miurahr/py7zr/releases/tag/v1.1.3
https://github.com/miurahr/py7zr/security/advisories/GHSA-h4gh-22qq-72r7
https://github.com/miurahr/py7zr/security/advisories/GHSA-h4gh-22qq-72r7

Configurations

No configuration.

History

09 Jul 2026, 16:16

Type	Values Removed	Values Added
References	~~() https://github.com/miurahr/py7zr/security/advisories/GHSA-h4gh-22qq-72r7 -~~	() https://github.com/miurahr/py7zr/security/advisories/GHSA-h4gh-22qq-72r7 -

08 Jul 2026, 21:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-08 21:16

Updated : 2026-07-10 19:07

NVD link : CVE-2026-55206

Mitre link : CVE-2026-55206

CVE.ORG link : CVE-2026-55206

JSON object : View

Products Affected

No product.

CWE

CWE-407

Inefficient Algorithmic Complexity

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