← Back
CVE-2026-23243
high
CVSS 7.8
Out-of-Bounds Write in Kernel (CVE-2026-23243)
Summary
out-of-bounds write in Kernel (CVE-2026-23243). Successful exploitation can lead to full system takeover. Mitigation: upgrade to `5.10.252, 5.15.202, 6.1.165, 6.6.128, 6.12.75, 6.18.14, 6.19.4` or later.
AI summary snake-internal / snake-material-v2
A vulnerability tracked as **CVE-2026-23243** has been found in Kernel.
Successful exploitation can lead to full system takeover. CVSS score: 7.8/10.
What to do: upgrade Kernel to **5.10.252, 5.15.202, 6.1.165, 6.6.128, 6.12.75, 6.18.14, 6.19.4** or later.
If unsure, ask your IT team or search "Kernel CVE-2026-23243" on the vendor's site.
CVE-2026-23243 (Kernel) — CWE-787 / CVSS v3 7.8
Attack vector: local / no user interaction
Patched: `5.10.252, 5.15.202, 6.1.165, 6.6.128, 6.12.75, 6.18.14, 6.19.4` — apply immediately
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
**out-of-bounds write** (CWE-787) exists in Kernel.
📍 Affected scope
Kernel — .
🔥 Severity
Severity: High (CVSS 7.8/10). Successful exploitation can lead to full system takeover
🔧 How to fix
Update to **5.10.252, 5.15.202, 6.1.165, 6.6.128, 6.12.75, 6.18.14, 6.19.4**.
🛡️ 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 'Kernel' .` 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 'Kernel' . | 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 `Kernel` を grep し、稼働しているサービス・バージョンを把握する。
-
6Apply patch patch
Upgrade Kernel to 5.10.252, 5.15.202, 6.1.165, 6.6.128, 6.12.75, 6.18.14, 6.19.4ステージング環境で 5.10.252, 5.15.202, 6.1.165, 6.6.128, 6.12.75, 6.18.14, 6.19.4 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスと、Step 3 で見つけた異常検知の続報チェックを含めること。
-
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。
Affected packages
Linux
Kernel
[{"type":"ECOSYSTEM","events":[{"introduced":"2.6.24"},{"fixed":"5.10.252"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.202"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.165"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.128"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.75"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.14"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"6.19.4"}]}]
References
- advisory https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/23xxx/CVE-2026-23243.json
- package https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- web https://git.kernel.org/stable/c/1371ef6b1ecf3676b8942f5dfb3634fb0648128e
- web https://git.kernel.org/stable/c/205955f29c26330b1dc7fdeadd5bb97c38e26f56
- web https://git.kernel.org/stable/c/362e45fd9069ffa1523f9f1633b606ebf72060d7
- web https://git.kernel.org/stable/c/52ab82cc5cf8ada5c3fb6ffe8f32fdb2fc27a34b
- web https://git.kernel.org/stable/c/5551b02fdbfd85a325bb857f3a8f9c9f33397ed2
- web https://git.kernel.org/stable/c/6eb2919474ca105c5b13d19574e25f0ddcf19ca2
- web https://git.kernel.org/stable/c/9c80d688f402539dfc8f336de1380d6b4ee14316
- web https://git.kernel.org/stable/c/a6a3e4af10993cb9e4b8f0548680aba0ab5f3b0d
- web https://nvd.nist.gov/vuln/detail/CVE-2026-23243
- web https://github.com/advisories/GHSA-85rq-57vx-88q2
- web https://cert-portal.siemens.com/productcert/html/ssa-019113.html
- web https://cert-portal.siemens.com/productcert/html/ssa-082556.html