filelock is a platform-independent file lock for Python. From 3.10.0 until 4.2.1, filelock on Windows ignores the mode argument for WindowsFileLock files and the ReadWriteLock SQLite database. A lock created with mode=0o600 receives the parent directory's inheritable ACL because _open_non_reparse_fd and _nt_open do not create an owner-only security descriptor. Another local account with inherited access can read holder metadata or the lock database, modify those files where the ACL permits writes, or take the byte-range lock after release and delay later acquisitions. UnixFileLock is not affected, and mutual exclusion between cooperating processes continues to hold. This issue is fixed in version 4.2.1.
Metrics
Affected Vendors & Products
Advisories
| Source | ID | Title |
|---|---|---|
Github GHSA |
GHSA-8mx5-7m5m-r77g | filelock: WindowsFileLock ignores mode: a 0o600 lock file and the ReadWriteLock database inherit the directory ACL |
Fixes
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
References
History
Fri, 06 Nov 2026 00:15:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Tox-dev
Tox-dev filelock |
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| Vendors & Products |
Tox-dev
Tox-dev filelock |
Thu, 05 Nov 2026 22:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | filelock is a platform-independent file lock for Python. From 3.10.0 until 4.2.1, filelock on Windows ignores the mode argument for WindowsFileLock files and the ReadWriteLock SQLite database. A lock created with mode=0o600 receives the parent directory's inheritable ACL because _open_non_reparse_fd and _nt_open do not create an owner-only security descriptor. Another local account with inherited access can read holder metadata or the lock database, modify those files where the ACL permits writes, or take the byte-range lock after release and delay later acquisitions. UnixFileLock is not affected, and mutual exclusion between cooperating processes continues to hold. This issue is fixed in version 4.2.1. | |
| Title | filelock: WindowsFileLock ignores mode: a 0o600 lock file and the ReadWriteLock database inherit the directory ACL | |
| Weaknesses | CWE-732 | |
| References |
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| Metrics |
cvssV3_1
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Projects
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Status: PUBLISHED
Assigner: GitHub_M
Published:
Updated: 2026-11-05T21:47:35.134Z
Reserved: 2026-10-19T20:16:09.857Z
Link: CVE-2026-112910
No data.
Status : Received
Published: 2026-11-05T22:17:46.877
Modified: 2026-11-05T22:17:46.877
Link: CVE-2026-112910
No data.
OpenCVE Enrichment
Updated: 2026-11-06T00:00:19Z
Weaknesses
Github GHSA