VulnerabilityPublished 11 Sep 2026Updated 5 Oct 2026

CVE-2026-89740: Linux kernel · serial: imx: serialize imx_uart_ports[] lifetime

Affects Linux kernelSource GCVE Database

Authoritative record:CVE-2026-89740

Not known to be exploited.

Data as of 26 Oct 2026, 14:05 UTC

Severity

Medium

Rated by Threat Radar · 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.

Exploitation evidence

Disclosed: evidence found.
CVE published 11 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

Affected software

Product	Affected	Fixed in
Ubuntu 26.04 LTSlinux`pkg:deb/ubuntu/linux?arch=source&distro=resolute`Other threats	Affected 6.17.0-5.5 – 7.0.0-38.38 23 affected builds	Fixed in–
Ubuntu 26.04 LTSlinux-aws`pkg:deb/ubuntu/linux-aws?arch=source&distro=resolute`Other threats	Affected 6.17.0-1002.2 – 7.0.0-1014.14 15 affected builds	Fixed in–
Ubuntu 26.04 LTSlinux-azure`pkg:deb/ubuntu/linux-azure?arch=source&distro=resolute`Other threats	Affected 6.17.0-1003.3 – 7.0.0-1017.17 15 affected builds	Fixed in–
Ubuntu 26.04 LTSlinux-azure-fde`pkg:deb/ubuntu/linux-azure-fde?arch=source&distro=resolute`Other threats	Affected 7.0.0-1003.3 – 7.0.0-1016.16 9 affected builds	Fixed in–
Ubuntu 26.04 LTSlinux-gcp`pkg:deb/ubuntu/linux-gcp?arch=source&distro=resolute`Other threats	Affected 6.17.0-1002.2 – 7.0.0-1014.14 13 affected builds	Fixed in–
Ubuntu 26.04 LTSlinux-gke`pkg:deb/ubuntu/linux-gke?arch=source&distro=resolute`Other threats	Affected 7.0.0-1002.3 – 7.0.0-1008.9 6 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

A fix has been implemented in the Linux kernel to properly serialize access to imx_uart_ports[] and clear entries after removal or failed addition. Users should apply the official kernel updates that include this patch. Since this is a kernel-level fix, upgrading to a patched kernel version is the recommended mitigation.

Description

A vulnerability in the Linux kernel's serial driver for imx UART ports was resolved. The issue involved improper serialization of the imx_uart_ports[] array lifetime, where a dangling pointer could remain after a failed port addition or removal. This allowed a sibling probe to register a shared console through a stale entry, potentially causing inconsistent or unintended behavior. The fix ensures the entry remains valid through removal and protects port addition and removal operations to prevent interleaving. Occupied slots are now rejected rather than overwritten during duplicate-line probes.

Impact

The vulnerability could lead to a sibling UART probe registering a shared console through a stale pointer, potentially causing incorrect device registration or console sharing. This may result in system instability or unexpected behavior in UART device management. There is no indication of remote code execution or privilege escalation from the provided data.

Summary

The Linux kernel vulnerability (CVE-2026-89740) affects the serial imx driver, specifically the management of the imx_uart_ports[] array. The imx_uart_probe() function published its devm-allocated port in the array before uart_add_one_port() completed, and if adding the port failed or after removal, the entry was not cleared, leaving a dangling pointer. This stale pointer could be used by a sibling probe to register a shared console improperly. The issue was reproduced under KASAN on QEMU mcimx6ul-evk by unbinding and rebinding UART devices. The patch keeps the entry valid through uart_remove_one_port(), clears it properly, and serializes port addition and removal to prevent race conditions. It also rejects attempts to overwrite an active port during duplicate-line probes.

References

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 25 Oct 2026, 03:27 UTC

Technical details

References

Community reviews

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