CVE-2026-23191

Published Feb 14, 2026

Last updated 5 days ago

CVSS high 7.8

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: ALSA: aloop: Fix racy access at PCM trigger The PCM trigger callback of aloop driver tries to check the PCM state and stop the stream of the tied substream in the corresponding cable. Since both check and stop operations are performed outside the cable lock, this may result in UAF when a program attempts to trigger frequently while opening/closing the tied stream, as spotted by fuzzers. For addressing the UAF, this patch changes two things: - It covers the most of code in loopback_check_format() with cable->lock spinlock, and add the proper NULL checks. This avoids already some racy accesses. - In addition, now we try to check the state of the capture PCM stream that may be stopped in this function, which was the major pain point leading to UAF.
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Modified
Products
linux_kernel

Risk scores

CVSS 3.1

Type
Primary
Base score
7
Impact score
5.9
Exploitability score
1
Vector string
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Severity
HIGH

Weaknesses

nvd@nist.gov
CWE-416
134c704f-9b21-4f2e-91b3-4a467353bcc0
CWE-362

Social media

Hype score
Not currently trending

  1. The kernel-rt CVEs (CVE-2025-68741, CVE-2026-23191) from April 2026 are just examples. Here’s how to check, patch, and mitigate – plus the book that turns you from a patcher into a vulnerability hunter. - > https://t.co/hBPHmBqpXb #AlmaLinux #Security https://t.co/QFw

    @Cezar_H_Linux

    26 Apr 2026

    212 Impressions

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Configurations

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References

Sources include official advisories and independent security research.