Use-After-Free in Linux kernel (CVE-2026-23171)
Summary
Vulnerability in Linux kernel (CVE-2026-23171). Successful exploitation can lead to full system takeover.
Original description
The description as published by the source.
In the Linux kernel, the following vulnerability has been resolved:
bonding: fix use-after-free due to enslave fail after slave array update
Fix a use-after-free which happens due to enslave failure after the new
slave has been added to the array. Since the new slave can be used for Tx
immediately, we can use it after it has been freed by the enslave error
cleanup path which frees the allocated slave memory. Slave update array is
supposed to be called last when further enslave failures are not expected.
Move it after xdp setup to avoid any problems.
It is very easy to reproduce the problem with a simple xdp_pass prog:
ip l add bond1 type bond mode balance-xor
ip l set bond1 up
ip l set dev bond1 xdp object xdp_pass.o sec xdp_pass
ip l add dumdum type dummy
Then run in parallel:
while :; do ip l set dumdum master bond1 1>/dev/null 2>&1; done;
mausezahn bond1 -a own -b rand -A rand -B 1.1.1.1 -c 0 -t tcp "dp=1-1023, flags=syn"
The crash happens almost immediately:
[ 605.602850] Oops: general protection fault, probably for non-canonical address 0xe0e6fc2460000137: 0000 [#1] SMP KASAN NOPTI
[ 605.602916] KASAN: maybe wild-memory-access in range [0x07380123000009b8-0x07380123000009bf]
[ 605.602946] CPU: 0 UID: 0 PID: 2445 Comm: mausezahn Kdump: loaded Tainted: G B 6.19.0-rc6+ #21 PREEMPT(voluntary)
[ 605.602979] Tainted: [B]=BAD_PAGE
[ 605.602998] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
[ 60…
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-2026-23171 has been found in Linux kernel.
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 kernel CVE-2026-23171" on the vendor's site.
CVE-2026-23171 (Linux kernel) — 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.
Use-after-free (CWE-416) exists in Linux kernel.
Check the vendor advisory for the affected versions of Linux kernel.
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
-
1Identify exposure identify
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで Linux kernel を使っているサービスとバージョンを洗い出す。
-
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。
Affected packages
Fix status by distribution
Fixed packages published by each distribution for this CVE
- BellSoft Alpaquita BELL-CVE-2026-23171 linux-lts
- Debian DEBIAN-CVE-2026-23171 linux
- Ubuntu UBUNTU-CVE-2026-23171 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 github.com