VulnerabilityPublished 28 Oct 2026Updated 29 Oct 2026

CVE-2026-99189: Linux kernel · gpio: mxc: fix race between chained IRQ handler install and probe completion

Affects Linux kernelSource GCVE Database

Compare

Authoritative record:CVE-2026-99189· Medium

Not known to be exploited.

Data as of 29 Oct 2026, 22:46 UTC

Severity

Medium

Rated by Threat Radar · CVSS not yet scored by NVD

Thin evidence

One scorer or none

Exploitation evidence

Disclosed: evidence found.
CVE published 28 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 29 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponized: A Metasploit exploit module or Exploit-DB entry exists (Metasploit scanner modules do not count), or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Affected software

Product	Affected	Fixed in
Ubuntu 26.10linux`pkg:deb/ubuntu/linux?arch=source&distro=stonking`Other threats	Affected 7.0.0-14.14 – 7.3.0-10.10 7 affected builds	Fixed in–
Ubuntu 26.10linux-aws`pkg:deb/ubuntu/linux-aws?arch=source&distro=stonking`Other threats	Affected 7.0.0-1004.4 – 7.3.0-1003.3 5 affected builds	Fixed in–
Ubuntu 26.10linux-azure`pkg:deb/ubuntu/linux-azure?arch=source&distro=stonking`Other threats	Affected 7.0.0-1004.4 – 7.3.0-1003.3 5 affected builds	Fixed in–
Ubuntu 26.10linux-azure-fde`pkg:deb/ubuntu/linux-azure-fde?arch=source&distro=stonking`Other threats	Affected =7.0.0-1004.4 =7.3.0-1002.3 =7.3.0-1003.4	Fixed in–
Ubuntu 26.10linux-gcp`pkg:deb/ubuntu/linux-gcp?arch=source&distro=stonking`Other threats	Affected 7.0.0-1003.3 – 7.3.0-1003.3 5 affected builds	Fixed in–
Ubuntu 26.10linux-oracle`pkg:deb/ubuntu/linux-oracle?arch=source&distro=stonking`Other threats	Affected 7.0.0-1003.3 – 7.3.0-1003.3 5 affected builds	Fixed in–

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

Apply the official fix that reorders the installation of the chained IRQ handler to after all dependencies are initialized and the port is added to the list. This prevents the handler from being active while data structures are incomplete and ensures it is not installed if probe fails. Since this is a kernel vulnerability, update to patched kernel versions as provided by the Linux distribution or vendor.

Description

A race condition vulnerability in the Linux kernel's gpio mxc driver was fixed. The issue involved installing a chained IRQ handler before necessary data structures were fully initialized, leading to potential use of NULL pointers or dangling handlers if interrupts occurred early or if probe steps failed. The fix moves handler installation to after all dependencies are ready, preventing the handler from being live while data structures are incomplete or from being installed if probe fails.

Impact

If an interrupt occurred during the vulnerable window, the kernel could dereference NULL pointers or access uninitialized data structures, potentially causing kernel crashes or undefined behavior. Furthermore, failure to unregister the chained handler on probe errors could leave dangling pointers, risking use-after-free conditions. However, no known exploits in the wild have been reported for this vulnerability.

Summary

CVE-2026-99189 addresses a race condition in the Linux kernel gpio mxc driver where mxc_update_irq_chained_handler() was called before the IRQ domain, generic IRQ chip, and port list entry were set up. This could cause mx3_gpio_irq_handler() to call generic_handle_domain_irq() with a NULL domain or mx2_gpio_irq_handler() to access an uninitialized port list. Additionally, failure in probe steps did not unregister the chained handler, leaving a dangling pointer to freed memory. The fix reorders the handler installation to occur only after all dependencies are initialized and the port is added to the list, ensuring the handler is never active with incomplete data structures or installed if probe fails.

References

Community reviews

Loading reviews…

Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 29 Oct 2026, 22:46 UTC

Technical details

References

Community reviews

Related threats