CVE-2026-43211

High

In the Linux kernel, the following vulnerability has been resolved: PCI: Fix pci_slot_trylock() error handling Commit a4e772898f8b ("PCI: Add missing bridge lock to pci_bus_lock()") delegates the bridge device's pci_dev_trylock() to pci_bus_trylock() in pci_slot_trylock(), but it forgets to remove the corresponding pci_dev_unlock() when pci_bus_trylock() fails. Before a4e772898f8b, the code did: if (!pci_dev_trylock(dev)) /* <- lock bridge device */ goto unlock; if (dev->subordinate) { if (!pci_bus_trylock(dev->subordinate)) { pci_dev_unlock(dev); /* <- unlock bridge device */ goto unlock; } } After a4e772898f8b the bridge-device lock is no longer taken, but the pci_dev_unlock(dev) on the failure path was left in place, leading to the bug. This yields one of two errors: 1. A warning that the lock is being unlocked when no one holds it. 2. An incorrect unlock of a lock that belongs to another thread. Fix it by removing the now-redundant pci_dev_unlock(dev) on the failure path. [Same patch later posted by Keith at https://patch.msgid.link/[email protected]]

Package Linux Kernel
Published 2026-05-06
Last modified 2026-05-11
CVSS version 3.1
Patch available
Yes

CVSS 3.1 score

7.8

out of 10
High
Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Weakness type

CWE-667

CVE-2026-43211 is a Improper Locking vulnerability

What is Improper Locking?

The product does not properly acquire or release a lock, which can lead to unexpected behaviour. Learn more on MITRE CWE

Affected versions

Linux kernel versions 5.10.226, 5.15.167, 6.1.110, 6.6.51, 4.19.322, 5.4.284, 6.10.10, 6.11 and later are affected. Fixed in 5.10.252, 5.15.202, 6.1.165, 6.6.128, 6.12.75, 6.18.16, 6.19.6, 7.0 and their respective stable series.

Affected from
≥ 5.10.226 ≥ 5.15.167 ≥ 6.1.110 ≥ 6.6.51 ≥ 4.19.322 ≥ 5.4.284 ≥ 6.10.10 ≥ 6.11
Fixed in
✓ 5.10.252 5.10.x ✓ 5.15.202 5.15.x ✓ 6.1.165 6.1.x ✓ 6.6.128 6.6.x ✓ 6.12.75 6.12.x ✓ 6.18.16 6.18.x ✓ 6.19.6 6.19.x ✓ 7.0

References

The following references provide additional information about CVE-2026-43211 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.

8 patch commits total View all on NVD

Frequently asked questions

  • What is CVE-2026-43211?

    CVE-2026-43211 is a High severity Linux kernel vulnerability with a CVSS score of 7.8 out of 10 , classified as an Improper Locking flaw (CWE-667) . It affects Linux kernel versions from 5.10.226 onward and has been patched in 5.10.252, 5.15.202, 6.1.165 and others. CVE-2026-43211 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

  • What is the CVSS score for CVE-2026-43211?

    CVE-2026-43211 has a CVSS score of 7.8 out of 10, rated High severity (CVSS 3.1). The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H .

  • Is there a patch available for CVE-2026-43211?

    Yes — CVE-2026-43211 has been patched. Fixed versions include 5.10.252, 5.15.202, 6.1.165 and others. If you are running Linux kernel 5.10.226 or later up to the fix versions, apply the relevant patch for your kernel branch.

  • Is CVE-2026-43211 actively exploited?

    No — CVE-2026-43211 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

  • What is Improper Locking (CWE-667)?

    The product does not properly acquire or release a lock, which can lead to unexpected behaviour. View CWE-667 on MITRE CWE →

Back to
All CVEs
View on
NVD / NIST