CVE-2025-39941

  1. OpenCVE
  2. Vulnerabilities (CVE)
  3. CVE-2025-39941
In the Linux kernel, the following vulnerability has been resolved: zram: fix slot write race condition Parallel concurrent writes to the same zram index result in leaked zsmalloc handles. Schematically we can have something like this: CPU0 CPU1 zram_slot_lock() zs_free(handle) zram_slot_lock() zram_slot_lock() zs_free(handle) zram_slot_lock() compress compress handle = zs_malloc() handle = zs_malloc() zram_slot_lock zram_set_handle(handle) zram_slot_lock zram_slot_lock zram_set_handle(handle) zram_slot_lock Either CPU0 or CPU1 zsmalloc handle will leak because zs_free() is done too early. In fact, we need to reset zram entry right before we set its new handle, all under the same slot lock scope.

7.8 /10

CVSS v3 : HIGH

V3 Legend

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References
Link Resource
https://git.kernel.org/stable/c/ce4be9e4307c5a60701ff6e0cafa74caffdc54ce Patch
https://git.kernel.org/stable/c/ff750e9f2c4d63854c33967d1646b5e89a9a19a2 Patch
Configurations

Configuration 1 (hide)

OR cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.17:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.17:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.17:rc3:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.17:rc4:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.17:rc5:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.17:rc6:*:*:*:*:*:*
History

19 Oct 2026, 21:10

Type Values Removed Values Added
Summary
  • (es) En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta: zram: corregir condición de carrera de escritura de slot Las escrituras concurrentes paralelas al mismo índice de zram resultan en handles de zsmalloc filtrados. Esquemáticamente podemos tener algo como esto: CPU0 CPU1 zram_slot_lock() zs_free(handle) zram_slot_lock() zram_slot_lock() zs_free(handle) zram_slot_lock() compress compress handle = zs_malloc() handle = zs_malloc() zram_slot_lock zram_set_handle(handle) zram_slot_lock zram_slot_lock zram_set_handle(handle) zram_slot_lock El handle de zsmalloc de la CPU0 o la CPU1 se filtrará porque zs_free() se ejecuta demasiado pronto. De hecho, necesitamos restablecer la entrada de zram justo antes de establecer su nuevo handle, todo bajo el mismo ámbito de bloqueo de slot.
Information

Published : 2025-10-04 08:15

Updated : 2026-10-19 21:10

NVD link : CVE-2025-39941

Mitre link : CVE-2025-39941

CVE.ORG link : CVE-2025-39941

JSON object : View

Products Affected

linux

  • linux_kernel
CWE
CWE-362

Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')