0.0
NA
CVE-2026-89942
iio: buffer: Fix potential use-after-free in anonymous buffer release
Description

In the Linux kernel, the following vulnerability has been resolved: iio: buffer: Fix potential use-after-free in anonymous buffer release An anonymous buffer handle holds a reference to the underlying IIO device. The reference is dropped in the buffer handle's release function. If the device has been removed, either through unbind or hot-unplug, the buffer handle might hold the last reference. The release function takes the mutex for the buffer using a guard, which means the unlock happens after all the code in the function, including `iio_device_put()`. If the anonymous buffer holds the last reference this might free both the IIO device and the buffer, which contains the mutex, leading to use-after-free when the mutex is unlocked. Fix this by using a scoped guard just around the buffer dmabuf list access, making sure the mutex is unlocked before releasing the IIO device. Version 10 of the patch that introduced this issue used this exact scheme of first unlocking and then dropping the reference [1]. During review it was suggested to use a guard instead, and version 11 made that change [2].

INFO

Published Date :

Sept. 16, 2026, 11:17 a.m.

Last Modified :

Sept. 16, 2026, 11:17 a.m.

Remotely Exploit :

No

Source :

416baaa9-dc9f-4396-8d5f-8c081fb06d67
Affected Products

The following products are affected by CVE-2026-89942 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

Solution
Fix use-after-free by ensuring mutex is unlocked before device release.
  • Update the Linux kernel to the patched version.
  • Apply the provided patch to the kernel source.
  • Ensure mutex is unlocked before releasing device reference.
References to Advisories, Solutions, and Tools
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-89942 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-89942 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-89942 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-89942 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    Sep. 16, 2026

    Action Type Old Value New Value
    Added Description In the Linux kernel, the following vulnerability has been resolved: iio: buffer: Fix potential use-after-free in anonymous buffer release An anonymous buffer handle holds a reference to the underlying IIO device. The reference is dropped in the buffer handle's release function. If the device has been removed, either through unbind or hot-unplug, the buffer handle might hold the last reference. The release function takes the mutex for the buffer using a guard, which means the unlock happens after all the code in the function, including `iio_device_put()`. If the anonymous buffer holds the last reference this might free both the IIO device and the buffer, which contains the mutex, leading to use-after-free when the mutex is unlocked. Fix this by using a scoped guard just around the buffer dmabuf list access, making sure the mutex is unlocked before releasing the IIO device. Version 10 of the patch that introduced this issue used this exact scheme of first unlocking and then dropping the reference [1]. During review it was suggested to use a guard instead, and version 11 made that change [2].
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/89xxx/CVE-2026-89942.json">CVE-2026-89942</a>
    Added Reference https://git.kernel.org/stable/c/6288b593e76eb10329326f2cd51e32557203b9e5
    Added Reference https://git.kernel.org/stable/c/6d4bdbf7bad63e759bf20259c527f69a1209e3dd
    Added Reference https://git.kernel.org/stable/c/ab53077511cde811bf3ee219426c522329c41226
    Added Reference https://git.kernel.org/stable/c/f1f8f0e8e0af9cae8150658dc7bb51332f984893
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.