๐Ÿ” CVE Alert

CVE-2026-112907

LOW 2.5

filelock: On Windows an oplock on a soft lock's marker holds SoftFileLock.acquire() past its timeout and blocks the stale break

CVSS Score
2.5
EPSS Score
0.0%
EPSS Percentile
0th

filelock is a platform-independent file lock for Python. From 3.22.0 until 4.2.1, soft lock classes on Windows read an existing marker with _read_lock_file and remove a stale marker through break_lock_file using pathname operations that wait for an oplock break. Another local account with read access to an unheld marker can keep a Level 1 or batch oplock unanswered, causing SoftFileLock.acquire and related async or fallback locks to wait beyond timeout, blocking=False, and cancel_check. A stale marker under the oplock cannot be broken, but mutual exclusion remains intact and no file other than the marker is accessed. This issue is fixed in version 4.2.1.

CWE CWE-667
Vendor tox-dev
Product filelock
Published Nov 5, 2026
Stay Ahead of the Next One

Get instant alerts for tox-dev filelock

Be the first to know when new low vulnerabilities affecting tox-dev filelock are published โ€” delivered to Slack, Telegram or Discord.

Get Free Alerts โ†’ Free ยท No credit card ยท 60 sec setup

CVSS v3 Breakdown

CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L
Attack Vector
Local
Attack Complexity
High
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
Low

Affected Versions

tox-dev / filelock
>= 3.22.0, < 4.2.1

References

NVD โ†— CVE.org โ†— EPSS Data โ†—
github.com: https://github.com/tox-dev/filelock/security/advisories/GHSA-567q-5qvw-pf92 github.com: https://github.com/tox-dev/filelock/pull/835 github.com: https://github.com/tox-dev/filelock/commit/97d694a9a3ee1721d6c79a480174dfd9b060a080 github.com: https://github.com/tox-dev/filelock/commit/e1e825b1992f69fb6b346dc395d5ae4893536c0a github.com: https://github.com/tox-dev/filelock/releases/tag/4.2.1