CVE-2026-43437

HIGH EPSS 2.6%
Published May 8, 20261mo ago · Modified Jun 17, 20262w ago
7.8 CVSS 3.1
High
Find Similar
Published May 8, 2026 1mo ago
Last Modified Jun 17, 2026 2w ago

Description

In the Linux kernel, the following vulnerability has been resolved: ALSA: pcm: fix use-after-free on linked stream runtime in snd_pcm_drain() In the drain loop, the local variable 'runtime' is reassigned to a linked stream's runtime (runtime = s->runtime at line 2157). After releasing the stream lock at line 2169, the code accesses runtime->no_period_wakeup, runtime->rate, and runtime->buffer_size (lines 2170-2178) — all referencing the linked stream's runtime without any lock or refcount protecting its lifetime. A concurrent close() on the linked stream's fd triggers snd_pcm_release_substream() → snd_pcm_drop() → pcm_release_private() → snd_pcm_unlink() → snd_pcm_detach_substream() → kfree(runtime). No synchronization prevents kfree(runtime) from completing while the drain path dereferences the stale pointer. Fix by caching the needed runtime fields (no_period_wakeup, rate, buffer_size) into local variables while still holding the stream lock, and using the cached values after the lock is released.

CVSS Details

Base Score
7.8
Exploitability
1.8
Impact
5.9
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack Vector Local
Attack Complexity Low
Privileges Required Low
User Interaction None
Scope Unchanged
Confidentiality High
Integrity High
Availability High

Threat Intelligence

EPSS Exploit Probability
2.6% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Weaknesses 1

CWE-416 Use After Free Memory Safety

Affected Products 9

VendorProductVersionRange
linuxlinux_kernel*≥3.0  –  <5.10.253
linuxlinux_kernel*≥5.11  –  <6.1.167
linuxlinux_kernel*≥6.2  –  <6.6.130
linuxlinux_kernel*≥6.7  –  <6.12.78
linuxlinux_kernel*≥6.13  –  <6.18.19
linuxlinux_kernel*≥6.19  –  <6.19.9
linuxlinux_kernel7.0any
linuxlinux_kernel7.0any
linuxlinux_kernel7.0any

References 7

  • git.kernel.org https://git.kernel.org/stable/c/4a758e9a1f5ed722f83c4dd35f867fe811553bcb
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/629cf09464cf98670996ea5c191dc9743e6f3f00
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/9b1dbd69ba6f8f8c69bc7b77c2ce3b9c6ed05ba6
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/9baee36e8c5443411c4629afabafaff8a46a23fd
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/ae8f8d30d334bad5b1b3cdb1eb8a0b771f55e432
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/c2f64e05a0587a83ec42dbd6b7a7ded79b2ff694
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/fc71f888994569f87d5bee20b1ac6c9c1e3a7a79
    Patch

Remediation

  • git.kernel.org https://git.kernel.org/stable/c/4a758e9a1f5ed722f83c4dd35f867fe811553bcb
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/629cf09464cf98670996ea5c191dc9743e6f3f00
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/9b1dbd69ba6f8f8c69bc7b77c2ce3b9c6ed05ba6
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/9baee36e8c5443411c4629afabafaff8a46a23fd
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/ae8f8d30d334bad5b1b3cdb1eb8a0b771f55e432
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/c2f64e05a0587a83ec42dbd6b7a7ded79b2ff694
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/fc71f888994569f87d5bee20b1ac6c9c1e3a7a79
    Patch