CVE-2026-89957s390/vfio-ap: Fix hot-unplug skipped when last AP adapter or domain removed
- 8.8HighCVSS base score
- 0.16%Exploitation in 30 daysEPSS · top 94% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
In the Linux kernel, the following vulnerability has been resolved: s390/vfio-ap: Fix hot-unplug skipped when last AP adapter or domain removed The vfio_ap_mdev_hot_unplug_cfg() function uses the return value of bitmap_andnot() to determine whether the guest APCB needs to be updated. However, bitmap_andnot() returns false when the resulting destination bitmap is empty. This means that if the only adapter, domain or control domain assigned to an mdev is removed from the host's AP configuration, the bit is correctly cleared from the shadow APCB, but bitmap_andnot() returns false because the result is an empty bitmap. Consequently, do_hotplug remains 0 and vfio_ap_mdev_update_guest_apcb() is never called, leaving the KVM guest with stale hardware access to the unplugged AP devices. Fix this by replacing the bitmap_andnot() return value check with bitmap_intersects() to determine whether the shadow APCB actually overlaps with the removal mask. If there is an intersection, call bitmap_andnot() solely for its side effect of clearing the bits, then unconditionally set do_hotplug to trigger the guest APCB update.
Timeline
ID reserved
By Linux
- 5 days later
· 5 days later
Published
- 33 days later
· 33 days later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| LinuxCNA (assigner) | 3.1 | High8.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H |
| NVDNVD · Received | 3.1 | High8.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.16% · top 94% of all CVEs (14 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.8.
Affected products
- affected eeb386aeb5b7c8d2dae6a3ba49255d8a97803182 – < f58e824de8577fe411f6199d659731a0f86a7275
- affected eeb386aeb5b7c8d2dae6a3ba49255d8a97803182 – < 3a9b049bbdc40165d7f3e20b818eec95e5694d96
- affected eeb386aeb5b7c8d2dae6a3ba49255d8a97803182 – < 753aa3bb1273bc0d36adb013d5915cc8ff6b72a9
- affected eeb386aeb5b7c8d2dae6a3ba49255d8a97803182 – < c45753c32d452d10d8efaeb52587e9e6e8126e33
- affected eeb386aeb5b7c8d2dae6a3ba49255d8a97803182 – < 04b35dd88c108b2d2ceaaa396aba1cb4049d5831
- affected eeb386aeb5b7c8d2dae6a3ba49255d8a97803182 – < 917f509bfb88048094dbb85c4e9dbc4d6fe4a886
- affected 6.0
- unaffected < 6.0
- unaffected 6.1.188 – ≤ 6.1.*
- unaffected 6.6.157 – ≤ 6.6.*
- unaffected 6.12.110 – ≤ 6.12.*
- unaffected 6.18.51 – ≤ 6.18.*
- unaffected 7.2.5 – ≤ 7.2.*
- unaffected 7.3 – ≤ *
References
References6
- https://git.kernel.org/stable/c/f58e824de8577fe411f6199d659731a0f86a7275 (opens in a new tab)
- https://git.kernel.org/stable/c/3a9b049bbdc40165d7f3e20b818eec95e5694d96 (opens in a new tab)
- https://git.kernel.org/stable/c/753aa3bb1273bc0d36adb013d5915cc8ff6b72a9 (opens in a new tab)
- https://git.kernel.org/stable/c/c45753c32d452d10d8efaeb52587e9e6e8126e33 (opens in a new tab)
- https://git.kernel.org/stable/c/04b35dd88c108b2d2ceaaa396aba1cb4049d5831 (opens in a new tab)
- https://git.kernel.org/stable/c/917f509bfb88048094dbb85c4e9dbc4d6fe4a886 (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-80557 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-89957)Record last updated .