High severity · published Mar 17, 2026
CVE-2026-3888
Local Privilege Escalation in snapd
7.8
CVSS
1.4%
EPSS
No
On KEV
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 vector
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
Attack vector
Local
Complexity
High
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)1.4% · higher than 72% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
U1
Ubuntu 16.04 LTS · Canonical
All versions, or not specified · source: vendor
U1
Ubuntu 18.04 LTS · Canonical
All versions, or not specified · source: vendor
U2
Ubuntu 20.04 LTS · Canonical
All versions, or not specified · source: vendor
U2
Ubuntu 22.04 LTS · Canonical
All versions, or not specified · source: vendor
U2
Ubuntu 24.04 LTS · Canonical
All versions, or not specified · source: vendor
UL
Ubuntu Linux · Canonical
16.04; 18.04; 20.04; 22.04; 24.04 · source: NVD
In the news
VulnerabilityHigh
CVE-2026-3888: Ubuntu Desktop 24.04+ vulnerable to Root exploit
Ubuntu flaw CVE-2026-3888 lets attackers gain root via a systemd timing exploit, affecting Desktop 24.04+ with high severity. Qualys researchers found a high-severity flaw, tracked as CVE-2026-3888 (CVSS score of 7.8), in Ubuntu Desktop 24.04+, which allows attackers to exploit a systemd cleanup timing issue to escalate privileges to root and potentially take full control […]
Mar 18, 2026·Security Affairs
VulnerabilityHigh
Ubuntu CVE-2026-3888 Bug Lets Attackers Gain Root via systemd Cleanup Timing Exploit
A high-severity security flaw affecting default installations of Ubuntu Desktop versions 24.04 and later could be exploited to escalate privileges to the root level.
Tracked as CVE-2026-3888 (CVSS score: 7.8), the issue could allow an attacker to seize control of a susceptible system.
"This flaw (CVE-2026-3888) allows an unprivileged local attacker to escalate privileges to full root access
Mar 18, 2026·The Hacker News
VulnerabilityCritical
CVE-2026-3888: Important Snap Flaw Enables Local Privilege Escalation to Root
The Qualys Threat Research Unit has identified a Local Privilege Escalation (LPE) vulnerability affecting default installations of Ubuntu Desktop version 24.04 and later. This flaw (CVE-2026-3888) allows an unprivileged local attacker to escalate privileges to full root access through the interaction of two standard system components: snap-confine and systemd-tmpfiles. While the exploit requires a specific […]
Mar 17, 2026·Qualys Blog
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-3888
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-3888
Mitigation
https://blog.qualys.com/vulnerabilities-threat-research/2026/03/17/cve-2026-3888-important-snap-flaw-enables-local-privilege-escalation-to-root
Third Party Advisory
https://cdn2.qualys.com/advisory/2026/03/17/snap-confine-systemd-tmpfiles.txt
Mitigation
https://discourse.ubuntu.com/t/snapd-local-privilege-escalation-cve-2026-3888
Third Party Advisory
https://ubuntu.com/security/CVE-2026-3888
Third Party Advisory
https://ubuntu.com/security/notices/USN-8102-1
Mailing List
http://www.openwall.com/lists/oss-security/2026/03/18/1
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