There is a defect in the CPython standard library module “mimetypes” where on Windows the default list of known file locations are writable meaning other users can create invalid files to cause MemoryError to be raised on Python runtime startup or have file extensions be interpreted as the incorrect file type. This defect is caused by the default locations of Linux and macOS platforms (such as “/etc/mime.types”) also being used on Windows, where they are user-writable locations (“C:\etc\mime.types”). To work-around this issue a user can call mimetypes.init() with an empty list (“[]”) on Windows platforms to avoid using the default list of known file locations.
Fix
Nothing published yet: no patch, vendor advisory or mitigation reference on NVD, no vendor advisory in the News for this CVE, not in CISA's KEV, no fixed package version. BaselineWatch does not guess at one.
Change history 4
- References+3 references (now 10)NVD modified 2026-10-26 01:17
- References+2 references (now 7)NVD modified 2026-10-17 02:17
- References+1 references (now 5)NVD modified 2026-10-16 03:17
- First seenCVSS 2.3NVD modified 2026-10-14 19:16
Affected (CPE criteria) 0
NVD has not attached CPE configurations yet.
References 10
- https://github.com/python/cpython/commit/04a29bf8f9ff8526cd96cb7368400173303a390a
- https://github.com/python/cpython/commit/2f00690fd5a75305e02c99628a41439179266f29
- https://github.com/python/cpython/commit/35dd324f6e30735162a68cde84bb04a169004325
- https://github.com/python/cpython/commit/5550519259656cbb8eeac09e3dbc0d5c248a4dea
- https://github.com/python/cpython/commit/76f4555c4ff10f5dda58d6528c17787df41e256c
- https://github.com/python/cpython/commit/8d4286a3f41d36f42c4b4cf5c4451a5a8c23fe87
- https://github.com/python/cpython/issues/159428
- https://mail.python.org/archives/list/[email protected]/thread/CDXW34ND2LSAOYAR5N6UNONP4ZBX4D6R/
- http://www.openwall.com/lists/oss-security/2025/02/14/8
- https://security.netapp.com/advisory/ntap-20250314-0001/