DEBIAN-CVE-2026-22701
filelock is a platform-independent file lock for Python. Prior to version 3.20.3, a TOCTOU race condition vulnerability exists in the SoftFileLock implementation of the filelock package. An attacker with local filesystem access and permission to create symlinks can exploit a race condition between the permission validation and file creation to cause lock operations to fail or behave unexpectedly. The vulnerability occurs in the _acquire() method between raise_on_not_writable_file() (permission check) and os.open() (file creation). During this race window, an attacker can create a symlink at the lock file path, potentially causing the lock to operate on an unintended target file or leading to denial of service. This issue has been patched in version 3.20.3.
DEBIAN-CVE-2026-22701
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: osv:DEBIAN-CVE-2026-22701
python-filelock
Source reference: /affected/0/package/name
- Affected versions
- 3.9.0-1
Source reference:
/affected/0/versions - Fixed versions
- 3.9.0-1+deb12u1
Source reference:
/affected/0/ranges - Prerequisites
- Not stated in this record
python-filelock
Source reference: /affected/1/package/name
- Affected versions
- 3.18.0-1
Source reference:
/affected/1/versions3.18.0-1+deb13u1Source reference:
/affected/1/versions3.19.1-1Source reference:
/affected/1/versions3.20.0-1Source reference:
/affected/1/versions3.20.2-1Source reference:
/affected/1/versions3.20.3-1Source reference:
/affected/1/versions3.24.3-1Source reference:
/affected/1/versions3.25.0-1Source reference:
/affected/1/versions3.25.2-1Source reference:
/affected/1/versions3.29.0-1Source reference:
/affected/1/versions3.29.4-1Source reference:
/affected/1/versions3.29.5-1Source reference:
/affected/1/versions3.29.7-1Source reference:
/affected/1/versions3.32.0-1Source reference:
/affected/1/versions3.32.2-1Source reference:
/affected/1/versions3.32.4-1Source reference:
/affected/1/versions3.32.4-2Source reference:
/affected/1/versions3.32.5-1Source reference:
/affected/1/versions3.32.6-1Source reference:
/affected/1/versions4.0.1-1Source reference:
/affected/1/versions - Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
python-filelock
Source reference: /affected/2/package/name
- Affected versions
- 3.18.0-1
Source reference:
/affected/2/versions3.19.1-1Source reference:
/affected/2/versions3.20.0-1Source reference:
/affected/2/versions3.20.2-1Source reference:
/affected/2/versions - Fixed versions
- 3.20.3-1
Source reference:
/affected/2/ranges - Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "3.9.0-1+deb12u1"
}
]
}
],
"package": {
"name": "python-filelock",
"purl": "pkg:deb/debian/python-filelock?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"versions": [
"3.9.0-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-22701.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "python-filelock",
"purl": "pkg:deb/debian/python-filelock?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"versions": [
"3.18.0-1",
"3.18.0-1+deb13u1",
"3.19.1-1",
"3.20.0-1",
"3.20.2-1",
"3.20.3-1",
"3.24.3-1",
"3.25.0-1",
"3.25.2-1",
"3.29.0-1",
"3.29.4-1",
"3.29.5-1",
"3.29.7-1",
"3.32.0-1",
"3.32.2-1",
"3.32.4-1",
"3.32.4-2",
"3.32.5-1",
"3.32.6-1",
"4.0.1-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-22701.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "3.20.3-1"
}
]
}
],
"package": {
"name": "python-filelock",
"purl": "pkg:deb/debian/python-filelock?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"versions": [
"3.18.0-1",
"3.19.1-1",
"3.20.0-1",
"3.20.2-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-22701.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
]Publisher severity
No explicit severity was provided.
- Event
- #57436 · Revision 1
- Added to Heist Feed
- Publisher date