Bug 2446109 (CVE-2026-23239)

Summary: CVE-2026-23239 kernel: Kernel: Race condition in espintcp can lead to denial of service
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedKeywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in the Linux kernel's espintcp component. A local attacker with low privileges could exploit a race condition in the espintcp_close() function. This could allow the espintcp_tx_work() worker to access freed memory, potentially leading to a system crash and resulting in a Denial of Service (DoS).
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Description OSIDB Bzimport 2026-03-10 18:03:39 UTC
In the Linux kernel, the following vulnerability has been resolved:

espintcp: Fix race condition in espintcp_close()

This issue was discovered during a code audit.

After cancel_work_sync() is called from espintcp_close(),
espintcp_tx_work() can still be scheduled from paths such as
the Delayed ACK handler or ksoftirqd.
As a result, the espintcp_tx_work() worker may dereference a
freed espintcp ctx or sk.

The following is a simple race scenario:

           cpu0                             cpu1

  espintcp_close()
    cancel_work_sync(&ctx->work);
                                     espintcp_write_space()
                                       schedule_work(&ctx->work);

To prevent this race condition, cancel_work_sync() is
replaced with disable_work_sync().