CVE-2026-3888
Local privilege escalation in snapd on Linux allows local attackers to get root privilege by re-creating snap's private /tmp directory when systemd-tmpfiles is configured to automatically clean up this directory.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.38%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
Local privilege escalation in snapd on Linux allows local attackers to get root privilege by re-creating snap's private /tmp directory when systemd-tmpfiles is configured to automatically clean up this directory. This issue affects Ubuntu 16.04 LTS, 18.04 LTS, 20.04 LTS, 22.04 LTS, and 24.04 LTS.
- CVSS 3.1
- 7.8 HIGHCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
- EPSS
- 0.38% probability · 32th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-268
- Affected
- canonical/ubuntu linux
- Source
- security@ubuntu.com
References
- https://blog.qualys.com/vulnerabilities-threat-research/2026/03/17/cve-2026-3888-important-snap-flaw-enables-local-privilege-escalation-to-rootMitigation, Third Party Advisory
- https://cdn2.qualys.com/advisory/2026/03/17/snap-confine-systemd-tmpfiles.txtThird Party Advisory
- https://discourse.ubuntu.com/t/snapd-local-privilege-escalation-cve-2026-3888Mitigation, Third Party Advisory
- https://ubuntu.com/security/CVE-2026-3888Third Party Advisory
- https://ubuntu.com/security/notices/USN-8102-1Third Party Advisory
- http://www.openwall.com/lists/oss-security/2026/03/18/1Mailing List, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.