Vulnerability in Ubuntu Linux (CVE-2026-3888)
Summary
Vulnerability in Ubuntu Linux (CVE-2026-3888). Successful exploitation can lead to full system takeover.
Original description
The description as published by the source.
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.
Source: NIST National Vulnerability Database NVD
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-3888 has been found in Ubuntu Linux.
Successful exploitation can lead to full system takeover. CVSS score: 7.8/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Ubuntu Linux CVE-2026-3888" on the vendor's site.
CVE-2026-3888 (Ubuntu Linux) — CWE-268 / CVSS v3 7.8
Attack vector: local / no user interaction
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-268) exists in Ubuntu Linux.
Check the vendor advisory for the affected versions of Ubuntu Linux.
Severity: High (CVSS 7.8/10). Successful exploitation can lead to full system takeover.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Audit SBOM/dependencies to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
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1Identify exposure identify
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで Ubuntu Linux を使っているサービスとバージョンを洗い出す。
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2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Debian DEBIAN-CVE-2026-3888 snapd
- Ubuntu UBUNTU-CVE-2026-3888 snapd Fixed in: 2.61.4ubuntu0.16.04.1+esm2
References
- advisory cdn2.qualys.com
- advisory discourse.ubuntu.com
- advisory ubuntu.com
- advisory github.com
- advisory nvd.nist.gov
- report ubuntu.com
- web blog.qualys.com
- web openwall.com
- web github.com
- web github.com
- web launchpad.net
- web launchpad.net
- web launchpad.net
- web launchpad.net
- web launchpad.net
- web launchpad.net