CVE-2025-8194
Tarfile infinite loop during parsing with negative member offset
CVSS Score
7.5
EPSS Score
0.2%
EPSS Percentile
48th
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
| CWE | CWE-835 |
| Vendor | python software foundation |
| Product | cpython |
| Published | Jul 28, 2025 |
| Last Updated | Apr 21, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
Affected Versions
Python Software Foundation / CPython
0 < 3.10.19 3.11.0 < 3.11.14 3.12.0 < 3.12.12 3.13.0 < 3.13.6 3.14.0a1 < 3.14.0rc2
References
github.com: https://github.com/python/cpython/issues/130577 github.com: https://github.com/python/cpython/pull/137027 mail.python.org: https://mail.python.org/archives/list/[email protected]/thread/ZULLF3IZ726XP5EY7XJ7YIN3K5MDYR2D/ github.com: https://github.com/python/cpython/commit/7040aa54f14676938970e10c5f74ea93cd56aa38 github.com: https://github.com/python/cpython/commit/cdae923ffe187d6ef916c0f665a31249619193fe gist.github.com: https://gist.github.com/sethmlarson/1716ac5b82b73dbcbf23ad2eff8b33e1 github.com: https://github.com/python/cpython/commit/c9d9f78feb1467e73fd29356c040bde1c104f29f github.com: https://github.com/python/cpython/commit/fbc2a0ca9ac8aff6887f8ddf79b87b4510277227 github.com: https://github.com/python/cpython/commit/57f5981d6260ed21266e0c26951b8564cc252bc2 github.com: https://github.com/python/cpython/commit/73f03e4808206f71eb6b92c579505a220942ef19 github.com: https://github.com/python/cpython/commit/b4ec17488eedec36d3c05fec127df71c0071f6cb openwall.com: http://www.openwall.com/lists/oss-security/2025/07/28/1 openwall.com: http://www.openwall.com/lists/oss-security/2025/07/28/2
Credits
🔍 Alexander Urieles Seth Larson Ethan Furman Steve Dower