What’s Vulnerable › Vulnerabilities
CVE-2025-8194: Tarfile infinite loop during parsing with negative member offset
- Severity: high (CVSS 7.5 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.7% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2025-07-28 · updated 2026-07-31
- Weakness: CWE-835
Description
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
Affected products
- Python: before 3.9.24; from 3.10.0 before 3.10.19; from 3.11.0 before 3.11.14; from 3.12.0 before 3.12.12; from 3.13.0 before 3.13.6; from 3.14.0a1 before 3.14.0rc2 — fixed in 3.10.19, 3.11.14, 3.12.12, 3.13.6, 3.14.0rc2, 3.9.24
How to fix
Upgrade to a fixed version: Python 3.10.19, 3.11.14, 3.12.12, 3.13.6. Check the vendor advisory for mitigations.
References
- https://gist.github.com/sethmlarson/1716ac5b82b73dbcbf23ad2eff8b33e1
- https://github.com/python/cpython/commit/57f5981d6260ed21266e0c26951b8564cc252bc2
- https://github.com/python/cpython/commit/7040aa54f14676938970e10c5f74ea93cd56aa38
- https://github.com/python/cpython/commit/73f03e4808206f71eb6b92c579505a220942ef19
- https://github.com/python/cpython/commit/b4ec17488eedec36d3c05fec127df71c0071f6cb
- https://github.com/python/cpython/commit/c9d9f78feb1467e73fd29356c040bde1c104f29f
- https://github.com/python/cpython/commit/cdae923ffe187d6ef916c0f665a31249619193fe
- https://github.com/python/cpython/commit/fbc2a0ca9ac8aff6887f8ddf79b87b4510277227
- https://github.com/python/cpython/issues/130577
- https://github.com/python/cpython/pull/137027
- https://mail.python.org/archives/list/security-announce@python.org/thread/ZULLF3IZ726XP5EY7XJ7YIN3K5MDYR2D/
- http://www.openwall.com/lists/oss-security/2025/07/28/1
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