MEDIUM · 4.7

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. Schemati...

Vulnerability Description

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.

CVSS Score

4.7

MEDIUM

CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack Vector
LOCAL
Attack Complexity
HIGH
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH

Affected Products

VendorProductVersions
LinuxLinux Kernel>= 6.14, < 6.16.9

Related Weaknesses (CWE)

References

FAQ

What is CVE-2025-39941?

CVE-2025-39941 is a vulnerability with a CVSS score of 4.7 (MEDIUM). 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. Schemati...

How severe is CVE-2025-39941?

CVE-2025-39941 has been rated MEDIUM with a CVSS base score of 4.7/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2025-39941?

Check the references section above for vendor advisories and patch information. Affected products include: Linux Linux Kernel.