VulnerabilityPublished 17 Sep 2026Updated 19 Oct 2026

CVE-2026-93091: Linux kernel · firmware: arm_scmi: Quiesce notifications before teardown

Affects Linux kernelSource CVE Database V5

Not known to be exploited · fixed in 6778bcabd2e0c32f73476f0bc6369013692540be : patch Linux kernel soon.

Data as of 26 Oct 2026, 16:39 UTC

Severity

High

Rated High by Threat Radar's AI analysis · CVSS not yet scored by NVD

EPSS: 0.2% chance of exploitation in 30 days – higher than 10% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 6778bcabd2e0c32f73476f0bc6369013692540be, 8e49055d0d495c9c07575ad8e111d9eaf0efb13f, 5e30d3d16d1a9e599be4dcea872874e65e2c277b +1

Exploitation evidence

Disclosed: evidence found.
CVE published 17 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: 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 26 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.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, 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

Upgrade Linux kernel to 6778bcabd2e0c32f73476f0bc6369013692540be, 8e49055d0d495c9c07575ad8e111d9eaf0efb13f, 5e30d3d16d1a9e599be4dcea872874e65e2c277b or 2aac23bc0a79af41104d99823bb250fae92ba144.

Affected software

Product	Affected	Fixed in
LinuxLinux	Affected ≥ 1e7cbfaa66d39e78bd24df0c78b55df68176b59e, < 6778bcabd2e0c32f73476f0bc6369013692540be	Fixed in 6778bcabd2e0c32f73476f0bc6369013692540be
LinuxLinux	Affected ≥ 1e7cbfaa66d39e78bd24df0c78b55df68176b59e, < 8e49055d0d495c9c07575ad8e111d9eaf0efb13f	Fixed in 8e49055d0d495c9c07575ad8e111d9eaf0efb13f
LinuxLinux	Affected ≥ 1e7cbfaa66d39e78bd24df0c78b55df68176b59e, < 5e30d3d16d1a9e599be4dcea872874e65e2c277b	Fixed in 5e30d3d16d1a9e599be4dcea872874e65e2c277b
LinuxLinux	Affected ≥ 1e7cbfaa66d39e78bd24df0c78b55df68176b59e, < 2aac23bc0a79af41104d99823bb250fae92ba144	Fixed in 2aac23bc0a79af41104d99823bb250fae92ba144
LinuxLinux	Affected =5.15	Fixed in–

AI-suggested

A fix is available and has been applied in specific commits identified by their hashes. Users should update to a Linux kernel version that includes these fixes. No additional mitigation is required beyond applying the official patch.

Description

CVE-2026-93091 is a use-after-free vulnerability in the Linux kernel's arm_scmi firmware component. It occurs because notification instances can be dereferenced after they have been freed during device removal or probe error paths. The flaw arises from improper ordering in teardown and late initialization work handling, leading to potential memory corruption.

Impact

Exploitation of this vulnerability could lead to kernel memory corruption due to use-after-free conditions, potentially causing system instability or crashes. There is no indication of known exploits in the wild. The impact is limited to affected Linux kernel versions with the arm_scmi firmware component.

Summary

This vulnerability in the Linux kernel's arm_scmi firmware interface involves the scmi_notification_exit() function clearing and releasing notification instances while transport callbacks may still deliver notifications. An RX interrupt during teardown can cause scmi_notify() to dereference freed memory. Additionally, the late-init worker queues work on the system workqueue without proper synchronization, allowing dereferencing of freed notification instances if the work is pending or running during resource release. The fix involves quiescing the notification core before tearing down TX/RX channels and using disable_work_sync() to ensure no late-init work is queued or running during teardown.

References

Community reviews

Loading reviews…

Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 26 Oct 2026, 14:47 UTC

Technical details

References

Community reviews

Related threats