← Back
CVE-2025-39691
high
CVSS 7.8
Use-After-Free in linux (CVE-2025-39691)
Summary
vulnerability in linux (CVE-2025-39691). Successful exploitation can lead to full system takeover.
AI summary snake-internal / snake-material-v2
A vulnerability tracked as **CVE-2025-39691** has been found in 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 "linux CVE-2025-39691" on the vendor's site.
CVE-2025-39691 (linux) — CWE-416 / 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.
❓ What is the problem
**use-after-free** (CWE-416) exists in linux.
📍 Affected scope
linux — .
🔥 Severity
Severity: High (CVSS 7.8/10). Successful exploitation can lead to full system takeover
🔧 How to fix
Update to the patched release per vendor advisory.
🛡️ Workaround
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
🔍 Detection
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run `grep -r 'linux' .` against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response Actions (7 steps)
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'linux' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で `linux` を grep し、稼働しているサービス・バージョンを把握する。
-
7Post-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 Step 3 と同じログクエリでアラート再発が無いか継続監視。
References
- web https://git.kernel.org/stable/c/03b40bf5d0389ca23ae6857ee25789f0e0b47ce8
- web https://git.kernel.org/stable/c/042cf48ecf67f72c8b3846c7fac678f472712ff3
- web https://git.kernel.org/stable/c/3169edb8945c295cf89120fc6b2c35cfe3ad4c9e
- web https://git.kernel.org/stable/c/70a09115da586bf662c3bae9c0c4a1b99251fad9
- web https://git.kernel.org/stable/c/7375f22495e7cd1c5b3b5af9dcc4f6dffe34ce49
- web https://git.kernel.org/stable/c/90b5193edb323fefbee0e4e5bc39ed89dcc37719
- web https://git.kernel.org/stable/c/c58c6b532b7b69537cfd9ef701c7e37cdcf79dc4
- web https://git.kernel.org/stable/c/c5aa6ba1127307ab5dc3773eaf40d73a3423841f
- web https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html
- web https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html
- web https://cert-portal.siemens.com/productcert/html/ssa-032379.html
- web https://nvd.nist.gov/vuln/detail/CVE-2025-39691
- web https://github.com/advisories/GHSA-6684-j5cx-q9qw