Is there a public exploit for CVE-2026-99231?

No public exploit for CVE-2026-99231 was found in Exploit-DB, Metasploit, Nuclei templates or public proof-of-concept repositories. That is an absence of evidence rather than proof that none exists.

How severe is CVE-2026-99231?

CVE-2026-99231 scores CVSS 7.8 (v3.1), rated high.

What does CVE-2026-99231 affect?

CVE-2026-99231 affects Linux Linux.

7.8 High

In the Linux kernel, the following vulnerability has been resolved: iouring/waitid: own the request before clearing ->head…

CVE-2026-99231

In the Linux kernel, the following vulnerability has been resolved: iouring/waitid: own the request before clearing ->head iowaitidremovewq() only takes the wait queue lock if ->head is set. iowaitidwait() clears ->head first thing, before it tries to become the owner of the request by bumping ->refs. If somebody else owns the request at that point, nothing keeps it from completing the request while the wake up handler is still going to touch it: CPU0 (iowaitidwait) CPU1 (iowaitid, holds a ref) listdelinit(&wait->entry) smpstorerelease(&iw->head, NULL) dowait() finds another child iowaitidremovewq() // ->head == NULL, no locking iowaitidfinish(), IOUCOMPLETE // request freed and reused atomicfetchinc(&iw->refs) The same goes for iowaitidcancel() if it claims the request in that window. ->refs is part of the per opcode data of the request, so this increments whatever the next user of the request keeps there. If that happens to be zero, the handler concludes that it owns the request, and queues iowaitidcb() for it. With the window held open by a delay, and the request reused for a receive that is waiting for data: BUG: KASAN: slab-use-after-free in wakeupcommon+0x1ca/0x1f0…

Assessment

CVSS: 7.8 (v3.1)
Severity: High
Known exploited: Not listed in CISA KEV
Exploit availability: Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
Published: 2 November 2026
Last updated: 2 November 2026
Affected: Linux · Linux
Assigner: Linux

CVSS vectorCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

At the source

EUVD (ENISA)

References

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