Bug 2513454 (CVE-2026-68177)

Summary: CVE-2026-68177 kernel: tracing: Delay module ref count for "enable_event" trigger
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
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 tracing module. When a module with an active enable/disable event is removed, its data can be accessed after it has been freed, leading to a use-after-free vulnerability. This could allow a local attacker to cause a denial of service or potentially escalate privileges.
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Description OSIDB Bzimport 2026-08-10 12:38:16 UTC 
In the Linux kernel, the following vulnerability has been resolved:

tracing: Delay module ref count for "enable_event" trigger

Triggers are now delayed from freeing, but can still be triggered until
after the RCU grace period has ended. The freeing of the enable_event data
is put into the private_data_free() callback, but the put of the module
refcount is done immediately.

It is possible that if a module is removed that has an event that would
enable (or disable) it is still active, it can read the data of the module
after it is removed causing a use-after-free bug.

Move the trace_event_put_ref() that releases the module into the delayed
callback so that the module can not be removed until any reference to its
events are finished.
Comment 1 Mauro Matteo Cascella 2026-08-11 11:30:37 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026081007-CVE-2026-68177-f0ae@gregkh/T