Vulnerability in Linux kernel (CVE-2026-64476)
Summary
Vulnerability in Linux kernel (CVE-2026-64476). 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:
vfio/pci: Latch disable_idle_d3 per device
When disable_idle_d3 was introduced in vfio-pci, it directly manipulated
the device power state with pci_set_power_state(). There were no
refcounts to maintain or balanced operations, we could unconditionally
bring the device to D0 and conditionally move it to D3hot. Therefore
the module parameter was made writable.
Later, in commit c61302aa48f7 ("vfio/pci: Move module parameters to
vfio_pci.c"), as part of the vfio-pci-core split, the writable aspect
of the module parameter was nullified. The parameter value could still
be changed through sysfs, but the vfio-pci driver latched the values
into vfio-pci-core globals at module init. Loading the vfio-pci module,
or unloading and reloading, with non-default or different values could
change the globals relative to existing devices bound to vfio-pci
variant drivers.
Runtime PM was introduced in commit 7ab5e10eda02 ("vfio/pci: Move the
unused device into low power state with runtime PM"), which marks the
point where power states became refcounted. PM get and put operations
need to be balanced, but the same module operations noted above can
change the global variables relative to those devices already bound to
vfio-pci variant drivers. This introduces a window where PM operations
can now become unbalanced.
To resolve this with a narrow footprint for stable backports, the
disable_idle_d3 flag is latched into the vf…
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-2026-64476 has been found in Linux kernel.
Risk of unauthorized operations or information disclosure.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Linux kernel CVE-2026-64476" on the vendor's site.
CVE-2026-64476 (Linux kernel)
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: ?. 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-2026-64476 linux-lts Fixed in: 6.1.182-r0
- Debian DEBIAN-CVE-2026-64476 linux Fixed in: 6.1.180-1
- Ubuntu UBUNTU-CVE-2026-64476 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 github.com