Bug 2467127 (CVE-2026-43272)

Summary: CVE-2026-43272 kernel: ring-buffer: Fix possible dereference of uninitialized pointer
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
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Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in the Linux kernel's ring-buffer component. This vulnerability allows a local user to potentially cause a denial of service. The issue occurs because a pointer in the rb_meta_validate_events() function is not properly initialized, and its dereference during a reader page validation failure can lead to system instability or a crash.
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Description OSIDB Bzimport 2026-05-06 13:05:44 UTC 
In the Linux kernel, the following vulnerability has been resolved:

ring-buffer: Fix possible dereference of uninitialized pointer

There is a pointer head_page in rb_meta_validate_events() which is not
initialized at the beginning of a function. This pointer can be dereferenced
if there is a failure during reader page validation. In this case the control
is passed to "invalid" label where the pointer is dereferenced in a loop.

To fix the issue initialize orig_head and head_page before calling
rb_validate_buffer.

Found by Linux Verification Center (linuxtesting.org) with SVACE.
Comment 1 Keith Grant 2026-05-07 00:06:57 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026050611-CVE-2026-43272-da4b@gregkh/T