filelock: SoftFileLock removes a live holder's marker when another user forges the PID in a writable marker
filelock is a platform-independent file lock for Python. From 3.22.0 until 4.2.1, SoftFileLock can trust a forged process identifier in a marker that an attacker can modify but cannot remove, allowing an authorized contender such as another process of the holder's account or root to act as a confused deputy, remove the live marker, and admit another holder. This issue is fixed in version 4.2.1.
CVE-2026-112939
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-112939
filelock
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"vendor": "tox-dev",
"product": "filelock",
"versions": [
{
"status": "affected",
"version": ">= 3.22.0, < 4.2.1"
}
]
}
]- Related CVEs
- CVE-2026-112939
Source reference:
/cveMetadata/cveId
Publisher severity
medium
Source reference: /containers/cna/metrics
- Event
- #42247 · Revision 1
- Added to Heist Feed
- Publisher date