CVE-2026-64430: Linux kernel · NTB: epf: Avoid calling pci_irq_vector() from hardirq context
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.5 High · fixed in 5.15.0-1117.124~20.04.1 : patch Linux kernel soon.
Data as of 28 Oct 2026, 11:50 UTC
- Patch
- Available – fixed in 5.15.0-1117.124~20.04.1, 5.15.0-1123.132~20.04.1, 5.15.0-1122.131~20.04.1 +59
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 25 Jul 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
Upgrade to a fixed release listed under Affected software.
Patches and advisories
- ubuntu.com/security/notices/USN-8726-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8727-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8728-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8760-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8726-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8726-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-8800-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8760-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8728-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8726-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-8728-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-8876-1 (opens in a new tab)
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 patch is available and has been released in Linux kernel versions 5.15.0-1117.124~20.04.1 and later. Users should update to these fixed kernel versions to remediate the issue. No additional mitigation is required as the fix addresses the root cause.
Description
CVE-2026-64430 is a vulnerability in the Linux kernel NTB (Non-Transparent Bridge) subsystem where the function ntb_epf_vec_isr() calls pci_irq_vector() from hardirq context. This call leads to a mutex lock inside pci_irq_vector(), causing a 'scheduling while atomic' kernel bug. The issue has been fixed in Linux kernel versions 5.15.0-1117.124~20.04.1 and later.
References
- ubuntu.com/security/CVE-2026-64430 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-64430 (opens in a new tab)
- git.kernel.org/linus/4dcddc1c794d1c65eda68f1f8dd04a0fecc0870f (opens in a new tab)
- git.kernel.org/stable/c/174a97f21bf9c54fa37ec0f321692e862ea130a3 (opens in a new tab)
- git.kernel.org/stable/c/1dba8444ac0100133d72374634f6d7451fff1ccc (opens in a new tab)
- git.kernel.org/stable/c/33bba331a4a5fee8b6026fe72eca13cceeec1b7b (opens in a new tab)
- git.kernel.org/stable/c/4dcddc1c794d1c65eda68f1f8dd04a0fecc0870f (opens in a new tab)
- git.kernel.org/stable/c/6350df503897d57c5634f71b0767d48c3b837583 (opens in a new tab)
- git.kernel.org/stable/c/aff271b12a1eb8c8b3da19223ae1a6abe1e8168b (opens in a new tab)
- git.kernel.org/stable/c/f71e8d9875069fa73e335f63f02ec6e52e3aaa51 (opens in a new tab)
- ubuntu.com/security/notices/USN-8726-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8727-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8728-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8760-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8726-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8726-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-8800-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8760-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8728-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8726-4 (opens in a new tab)