Bug 2516748 (CVE-2026-74433)

Summary: CVE-2026-74433 kernel: rxrpc: Fix UAF in rxgk_issue_challenge()
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
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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 rxrpc component, specifically within the `rxgk_issue_challenge()` function. This Use-After-Free (UAF) vulnerability occurs because a memory page containing challenge content is prematurely freed before a tracepoint invocation, causing a pointer to reference freed memory. This could allow a local attacker to potentially cause a denial of service or achieve arbitrary code execution.
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Description OSIDB Bzimport 2026-08-15 06:31:29 UTC 
In the Linux kernel, the following vulnerability has been resolved:

rxrpc: Fix UAF in rxgk_issue_challenge()

Fix rxgk_issue_challenge() to free the page containing the challenge
content after invoking the tracepoint as the whdr passed to the tracepoint
points into the page just freed.
Comment 1 Keith Grant 2026-08-20 22:50:53 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026081515-CVE-2026-74433-cada@gregkh/T