CVE-2026-53243 (GCVE-0-2026-53243)

Vulnerability from cvelistv5 – Published: 2026-06-25 08:39 – Updated: 2026-06-25 08:39
VLAI
Title
rseq: Fix using an uninitialized stack variable in rseq_exit_user_update()
Summary
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.
Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Assigner
Linux CNA under the mitre root
CNA scorecard D 53/100 over 7033 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: d242126fd21ab8f1631fdbc8589e43a9d4229f3b , < e12d20a63b61aaf9de4772effccf42cc9a003e58 (git)
Affected: 82f572449cfe75f12ea985986da60e11f308f77d , < 6d99479799c69c3cb588fcda19c81d8f61d64ecd (git)
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Linux Linux Affected: 7.0.10 , < 7.0.13 (semver)
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Show details on NVD website
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