Vulnerability in Kernel (CVE-2026-23399)
Summary
Vulnerability in Kernel (CVE-2026-23399). Risk of unauthorized operations or information disclosure. Mitigation: upgrade to 6.12.78, 6.18.20, 6.19.10 or later.
Original description
The description as published by the source.
In the Linux kernel, the following vulnerability has been resolved:
nf_tables: nft_dynset: fix possible stateful expression memleak in error path
If cloning the second stateful expression in the element via GFP_ATOMIC
fails, then the first stateful expression remains in place without being
released.
unreferenced object (percpu) 0x607b97e9cab8 (size 16):
comm "softirq", pid 0, jiffies 4294931867
hex dump (first 16 bytes on cpu 3):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
backtrace (crc 0):
pcpu_alloc_noprof+0x453/0xd80
nft_counter_clone+0x9c/0x190 [nf_tables]
nft_expr_clone+0x8f/0x1b0 [nf_tables]
nft_dynset_new+0x2cb/0x5f0 [nf_tables]
nft_rhash_update+0x236/0x11c0 [nf_tables]
nft_dynset_eval+0x11f/0x670 [nf_tables]
nft_do_chain+0x253/0x1700 [nf_tables]
nft_do_chain_ipv4+0x18d/0x270 [nf_tables]
nf_hook_slow+0xaa/0x1e0
ip_local_deliver+0x209/0x330
Source: NIST National Vulnerability Database NVD GitHub Advisory
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-2026-23399 has been found in Kernel.
Risk of unauthorized operations or information disclosure. CVSS score: 5.5/10.
What to do: upgrade Kernel to 6.12.78, 6.18.20, 6.19.10 or later.
If unsure, ask your IT team or search "Kernel CVE-2026-23399" on the vendor's site.
CVE-2026-23399 (Kernel) — CWE-401 / CVSS v3 5.5
Attack vector: local / no user interaction
Patched: 6.12.78, 6.18.20, 6.19.10 — 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.
A vulnerability (CWE-401) exists in Kernel.
Check the vendor advisory for the affected versions of Kernel.
Severity: Medium (CVSS 5.5/10). Risk of unauthorized operations or information disclosure.
Update to 6.12.78, 6.18.20, 6.19.10.
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. Run grep -r 'Kernel' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
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。 -
2Apply patch patch
Upgrade Kernel to 6.12.78, 6.18.20, 6.19.10ステージング環境で 6.12.78, 6.18.20, 6.19.10 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を含めること。
-
3Post-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。
Affected packages
Fix status by distribution
Fixed packages published by each distribution for this CVE
- BellSoft Alpaquita BELL-CVE-2026-23399 linux-lts Fixed in: 6.1.175-r0
- Debian DEBIAN-CVE-2026-23399 linux Fixed in: 6.1.176-1
- Ubuntu UBUNTU-CVE-2026-23399 linux-hwe-edge
References
- advisory nvd.nist.gov
- advisory github.com
- package git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web github.com
- web cert-portal.siemens.com
- web cert-portal.siemens.com
- web cert-portal.siemens.com