CVE-2026-89448: Linux kernel · iommu/vt-d: Force requesting ACS when tboot is enabled
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 9.3 Critical.
Data as of 26 Oct 2026, 12:55 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 3% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/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 to address this issue by updating detect_intel_iommu() to check for tboot and force ACS request accordingly. Users should apply the official Linux kernel updates that include this fix. No additional mitigation steps are indicated.
Description
In the Linux kernel, the following vulnerability has been resolved: iommu/vt-d: Force requesting ACS when tboot is enabled Currently the conditions of requesting ACS in detect_intel_iommu() don't include tboot, leading to a possible misconfiguration with ACS disabled (e.g. due to user opts) while iommu is later forced on by tboot_force_iommu(). Fix it by checking tboot in detect_intel_iommu().
References
- nvd.nist.gov/vuln/detail/CVE-2026-89448 (opens in a new tab)
- git.kernel.org/stable/c/45705a6bfdb283f7b3b509010fd617b72f942537 (opens in a new tab)
- git.kernel.org/stable/c/607432b2618b61df81134be0ef2562b8300c1216 (opens in a new tab)
- git.kernel.org/stable/c/87bc611c6c98a41c00feb7b06b0c297dd141a2ae (opens in a new tab)
- git.kernel.org/stable/c/aaeb81241e802c86be69394f72d49fde3f861fbb (opens in a new tab)
- ubuntu.com/security/CVE-2026-89448 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-89448 (opens in a new tab)
- git.kernel.org/linus/607432b2618b61df81134be0ef2562b8300c1216 (opens in a new tab)