Vulnerability in Linux kernel (CVE-2026-43191)
Summary
Vulnerability in Linux kernel (CVE-2026-43191). Risk of unauthorized operations or information disclosure.
Original description
The description as published by the source.
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Adjust PHY FSM transition to TX_EN-to-PLL_ON for TMDS on DCN35
[Why]
A backport of the change made for DCN401 that addresses an issue where
we turn off the PHY PLL when disabling TMDS output, which causes the
OTG to remain stuck.
The OTG being stuck can lead to a hang in the DCHVM's ability to ACK
invalidations when it thinks the HUBP is still on but it's not receiving
global sync.
The transition to PLL_ON needs to be atomic as there's no guarantee
that the thread isn't pre-empted or is able to complete before the
IOMMU watchdog times out.
[How]
Backport the implementation from dcn401 back to dcn35.
There's a functional difference in when the eDP output is disabled in
dcn401 code so we don't want to utilize it directly.
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-2026-43191 has been found in Linux kernel.
Risk of unauthorized operations or information disclosure. CVSS score: 5.5/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Linux kernel CVE-2026-43191" on the vendor's site.
CVE-2026-43191 (Linux kernel) — CVSS v3 5.5
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: Medium (CVSS 5.5/10). Risk of unauthorized operations or information disclosure.
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-2026-43191 linux-lts
- Debian DEBIAN-CVE-2026-43191 linux
- Ubuntu UBUNTU-CVE-2026-43191 linux
References
- advisory nvd.nist.gov
- advisory github.com
- package git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web github.com
- web git.kernel.org