CVE-2026-44722 (GCVE-0-2026-44722)

Vulnerability from cvelistv5 – Published: 2026-07-17 16:42 – Updated: 2026-07-17 17:25
VLAI
Title
pyzipper: Encryption bypass for small files encrypted with pyzipper
Summary
pyzipper is a replacement for Python's zipfile that can read and write AES encrypted zip files. Prior to 0.4.0, a Python operator precedence bug in pyzipper/zipfile_aes.py caused the AE-2 format to never be automatically selected during encryption, causing encrypted entries to be written in AE-1 format and exposing the plaintext CRC32 checksum in the ZIP header and, for unseekable zip archives, in the datadescripter section, allowing an attacker who possesses the archive to brute-force candidate plaintexts for small or low-entropy files by comparing CRC32 values. This issue is fixed in version 0.4.0.
Severity
6.2 (Medium)
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-17 17:25 UTC
CWE
  • CWE-480 - Use of Incorrect Operator
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7994 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
danifus pyzipper Affected: < 0.4.0
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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