CVE-2026-53243

In the Linux kernel, the following vulnerability has been resolved: rseq: Fix using an uninitialized stack variable in rseq_exit_user_update() There is an bug in which an uninitialized stack variable is used in rseq_exit_user_update() as reported by syzbot: BUG: KMSAN: kernel-infoleak in rseq_set_ids_get_csaddr include/linux/rseq_entry.h:502 [inline] The local variable: struct rseq_ids ids = { .cpu_id = task_cpu(t), .mm_cid = task_mm_cid(t), .node_id = cpu_to_node(ids.cpu_id), }; According to the C standard, the evaluation order of expressions in an initializer list is indeterminately sequenced. The compiler (Clang, in this KMSAN build) evaluates `cpu_to_node(ids.cpu_id)` *before* `ids.cpu_id` is initialized with `task_cpu(t)`. This is fixed by moving the assignment of ids.node_id outside the structure initialization.

CVSS v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

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/6d99479799c69c3cb588fcda19c81d8f61d64ecd	Patch
https://git.kernel.org/stable/c/e12d20a63b61aaf9de4772effccf42cc9a003e58	Patch

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel:7.1:rc3::::::
	cpe:2.3:o:linux:linux_kernel:7.1:rc4::::::
	cpe:2.3:o:linux:linux_kernel:7.1:rc5::::::
	cpe:2.3:o:linux:linux_kernel:7.1:rc6::::::

History

No history.

Information

Published : 2026-06-25 09:16

Updated : 2026-07-07 22:21

NVD link : CVE-2026-53243

Mitre link : CVE-2026-53243

CVE.ORG link : CVE-2026-53243

JSON object : View

Products Affected

linux

linux_kernel

CWE

CWE-908

Use of Uninitialized Resource

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