CVE-2026-80991: Linux kernel · net: ravb: serialize PTP clock teardown
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.8 High.
Data as of 26 Oct 2026, 14:05 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 5% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 11 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.04 LTSlinuxpkg:deb/ubuntu/linux?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-gkepkg:deb/ubuntu/linux-gke?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A fix has been implemented in the Linux kernel source code that uses atomic operations and IRQ synchronization to prevent the race condition. Users should update to the patched kernel version once available. Patch status is not explicitly confirmed here; check the official Linux kernel advisories or vendor updates for the fixed versions.
Description
In the Linux kernel, the following vulnerability has been resolved: net: ravb: serialize PTP clock teardown ravb_ptp_interrupt() can race with ravb_ptp_stop() and pass the clock to ptp_clock_event() while ptp_clock_unregister() is freeing it. This can lead to a use-after-free. Use READ_ONCE() and WRITE_ONCE() for lockless access to the clock pointer. Atomically detach it with xchg() before disabling PTP interrupts, then synchronize all IRQs which can invoke ravb_ptp_interrupt() before unregistering the detached clock. A handler which read the old pointer completes before the clock is unregistered, while later handlers read NULL and skip the event.
References
- nvd.nist.gov/vuln/detail/CVE-2026-80991 (opens in a new tab)
- git.kernel.org/stable/c/1cb9663789c5b7a12fcd419fcca6d6254c398252 (opens in a new tab)
- git.kernel.org/stable/c/66b50c31419e7946e9aa325a468ad9b64c961a25 (opens in a new tab)
- git.kernel.org/stable/c/67a82e6f886beed0de8f8da08bb767e68fba952d (opens in a new tab)
- git.kernel.org/stable/c/695acb5534a9e366efb47b40c7487fc56488b09b (opens in a new tab)
- ubuntu.com/security/CVE-2026-80991 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-80991 (opens in a new tab)
- git.kernel.org/linus/1cb9663789c5b7a12fcd419fcca6d6254c398252 (opens in a new tab)