CVE-2026-53243
Description
A flaw was found in the Linux kernel. An uninitialized stack variable in the rseq_exit_user_update() function can lead to an information leak. This occurs due to an indeterminate sequencing of expressions during the initialization of the rseq_ids structure, where ids.node_id is assigned using an uninitialized ids.cpu_id. A local attacker could potentially exploit this to gain sensitive kernel information.
Understanding the Weakness (CWE)
Confidentiality
Technical Impact: Read Memory; Read Application Data
When reusing a resource such as memory or a program variable, the original contents of that resource may not be cleared before it is sent to an untrusted party.
Availability
Technical Impact: DoS: Crash, Exit, or Restart
The uninitialized resource may contain values that cause program flow to change in ways that the programmer did not intend.
Frequently Asked Questions
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