CVE-2026-3888 — Local Privilege Escalation in snapd

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

• Documented mitigation — blog.qualys.com (NIST National Vulnerability Database)
• Documented mitigation — discourse.ubuntu.com (NIST National Vulnerability Database)

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

1. Identify exposed assets running the affected vendor/product/version combinations (Canonical Ubuntu 16.04 LTS, Canonical Ubuntu 18.04 LTS, Canonical Ubuntu 20.04 LTS…).
2. Apply the documented mitigations until a definitive fix is available.
3. Search available logs for exploit probes, errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-268

Other CVEs with this weakness →

Public exploits, PoCs and detection templates

Public code that demonstrates or tests the flaw raises the odds of mass exploitation — and Nuclei templates help find vulnerable assets in your environment.

Warning: public PoCs are sometimes disguised malware. Use them only for authorized testing in an isolated environment. This portal does not host exploit code — it only points to the sources.

EPSS over time FIRST

Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.48%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

• Local/physical vector: focus on endpoint telemetry (EDR) from affected hosts.

Timeline

What happened to this CVE, newest first.

• 2026
• Affected products added · canonical/ubuntu 16.04 lts, canonical/ubuntu 18.04 lts, canonical/ubuntu 20.04 lts, canonical/ubuntu 22.04 lts, canonica
  Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
• SSVC assessment updated
  Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
• Record published
  Oct 13, 2026
• Fix documented
  Oct 13, 2026 · NIST National Vulnerability Database
• CVSS changed · 7.8
  Oct 13, 2026 · NIST National Vulnerability Database
• Source status changed · → Analyzed
  Oct 13, 2026 · NIST National Vulnerability Database
• Record created in this database
  Oct 13, 2026 · NIST National Vulnerability Database
• CVE published
  Mar 17, 2026 · canonical

Source activity

Repeated readings are counted rather than listed.

• 1× Official description updated · Oct 13, 2026 – Oct 13, 2026

References

6 on the record

• blog.qualys.com/vulnerabilities-threat-research/2026/03/17/cve-2026-3888-important-sn
  Mitigation, Third Party Advisory, technical-description, media-coverage, NIST National Vulnerability Database
• discourse.ubuntu.com/t/snapd-local-privilege-escalation-cve-2026-3888
  Mitigation, Third Party Advisory, technical-description, vendor-advisory, NIST National Vulnerability Database
• ubuntu.com/security/CVE-2026-3888
  Third Party Advisory, vdb-entry, issue-tracking, NIST National Vulnerability Database
• www.openwall.com/lists/oss-security/2026/03/18/1
  Mailing List, Third Party Advisory, NIST National Vulnerability Database
• ubuntu.com/security/notices/USN-8102-1
  Third Party Advisory, vendor-advisory, NIST National Vulnerability Database
• cdn2.qualys.com/advisory/2026/03/17/snap-confine-systemd-tmpfiles.txt
  Third Party Advisory, technical-description, media-coverage, NIST National Vulnerability Database

Elsewhere on this site

Related CVEs (same products)

• High CVE-2026-8933 snap-confine Local Privilege Escalation via Capabilities Misconfiguration or Flaw in Execution Environment Setup Jul 21, 2026
• High CVE-2026-15226 snapd snap-confine Sandbox Confinement Bypass via Omission of setuid Restriction in Seccomp Templates Jul 21, 2026
• Medium CVE-2024-5300 AppArmor Base Profile Misconfiguration in snapd Permits Confined Snaps Unauthorized Access to Hashed Passwords via systemd-userdbd Jul 21, 2026
• Medium CVE-2026-9494 ubuntu-pro-client Information Disclosure via Cleartext Bearer Token Exposure in Process Command Line Jul 16, 2026
• Critical CVE-2026-11386 ubuntu-pro-client Input Validation Vulnerability Leading to Arbitrary APT Directive Injection and Remote Code Execution Jul 16, 2026
• Medium CVE-2026-12391 ubuntu-pro-client Local Privilege Escalation and Information Disclosure via Symlink Arbitrary File Read in collect-logs Jul 16, 2026

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

• No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
• No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
• No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-3888 is "Local Privilege Escalation in snapd", rated High. It affects Ubuntu 16.04 LTS (Canonical); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 7.8 describes technical severity. EPSS 0.48% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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