SB2025101418 - Improper input validation in Python zipfile module
Published: October 14, 2025
Security Bulletin ID
SB2025101418
Severity
Medium
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Remote access
Highest impact
Data manipulation
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 security vulnerability.
1) Input validation error (CVE-ID: CVE-2025-8291)
The vulnerability allows a remote attacker to extract files into arbitrary locations on the system.
The vulnerability exists due to the zipfile module does not check the validity of the ZIP64 End of Central Directory (EOCD) Locator record offset value when extracting files. A remote attacker can use a specially crafted zip file to extract data into arbitrary locations on the system.
Remediation
Install update from vendor's website.
References
- https://github.com/python/cpython/commit/162997bb70e067668c039700141770687bc8f267
- https://github.com/python/cpython/commit/1d29afb0d6218aa8fb5e1e4a6133a4778d89bb46
- https://github.com/python/cpython/commit/333d4a6f4967d3ace91492a39ededbcf3faa76a6
- https://github.com/python/cpython/commit/76437ac248ad8ca44e9bf697b02b1e2241df2196
- https://github.com/python/cpython/commit/8392b2f0d35678407d9ce7d95655a5b77de161b4
- https://github.com/python/cpython/commit/bca11ae7d575d87ed93f5dd6a313be6246e3e388
- https://github.com/python/cpython/commit/d11e69d6203080e3ec450446bfed0516727b85c3
- https://github.com/python/cpython/issues/139700
- https://github.com/python/cpython/pull/139702
- https://mail.python.org/archives/list/security-announce@python.org/thread/QECOPWMTH4VPPJAXAH2BGTA4XADOP62G/