Vulnerability in Linux kernel (CVE-2026-89741)
Summary
Vulnerability in Linux kernel (CVE-2026-89741). 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:
Revert "media: v4l2-dev: fix error handling in __video_register_device()"
This reverts commit 2a934fdb01db6458288fc9386d3d8ceba6dd551a.
The intentions of that patch were good, but it doesn't work.
The idea is that if device_register fails, you have to do a put_device
to let the ref counter release resources.
However, the V4L2 API says that if video_register_device() fails, then
you have to call video_device_release(), which kfree()s the video_device
struct.
But the put_device() will already have freed the struct, so you end
up in a double-free scenario.
There is not really a good way of fixing this without breaking
video_register_device() into two parts, one that initializes everything,
and one that does the actual device_register, and then converting all
V4L2 drivers to this new model.
That is a massive job, and it is very unlikely that device_register
will fail.
So rather than ending up in a double-free scenario, just revert this
patch, and in that case we'll have a small memory leak. Which is a lot
more robust.
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-2026-89741 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-2026-89741" on the vendor's site.
CVE-2026-89741 (Linux kernel) — 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 (unclassified) 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
- Ubuntu UBUNTU-CVE-2026-89741 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 git.kernel.org
- web github.com