CVE-2025-8194 HIGH

CVE-2025-8194: Tarfile infinite loop during parsing with negative member offset

Vendor Python Software Foundation
Product CPython
Weakness CWE-835
Published July 28, 2025
Last update April 21, 2026

CVSS base score

7.5/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality None
Integrity None

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

What the vulnerability does

01Description

There is a defect in the CPython “tarfile” module affecting the “TarFile” extraction and entry enumeration APIs. The tar implementation would process tar archives with negative offsets without error, resulting in an infinite loop and deadlock during the parsing of maliciously crafted tar archives. This vulnerability can be mitigated by including the following patch after importing the “tarfile” module:  https://gist.github.com/sethmlarson/1716ac5b82b73dbcbf23ad2eff8b33e1

Key dates

02Disclosure timeline

July 28, 2025 CVE published
April 21, 2026 Record updated