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.

CVSS v3 4.7 MEDIUM

4.7^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.0 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

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

No history.

Information

Published : 2025-10-04 08:15

Updated : 2026-01-23 20:37

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')

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