CVE-2026-64151: Linux kernel · iommupt: Check for missing PAGE_SIZE in the pgsize_bitmap
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 8.4 High · fixed in 7.0.0-28.28~24.04.1 : patch Linux kernel soon.
Data as of 26 Oct 2026, 13:47 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.
- Patch
- Available – fixed in 7.0.0-28.28~24.04.1, 7.0.0-28.28, 7.0.0-1008.8 +3
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:NExploitation evidence
Disclosed: evidence found.
CVE published 20 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.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.04 LTSlinuxpkg:deb/ubuntu/linux@7.0.0-28.28?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-awspkg:deb/ubuntu/linux-aws@7.0.0-1009.9?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure@7.0.0-1009.9?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-azure-fdepkg:deb/ubuntu/linux-azure-fde@7.0.0-1008.8?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-gcppkg:deb/ubuntu/linux-gcp@7.0.0-1008.8?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-gkepkg:deb/ubuntu/linux-gke@7.0.0-1003.4?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
An official patch is available and should be applied to affected Linux kernel versions to remediate this vulnerability. The fix is included in the Linux kernel updates referenced by the vendor advisory (Ubuntu Security Notice USN-8593-1). Systems running affected versions should be updated promptly. No additional mitigation actions are specified or required beyond applying the official fix.
Description
A vulnerability in the Linux kernel's iommupt driver was fixed, addressing a missing PAGE_SIZE check in the pgsize_bitmap. This issue, while technically allowed, was against design and could lead to improper iommu_domain usage with the DMA API. The flaw was corrected by adjusting the code to skip the fast path when PAGE_SIZE is missing. The vulnerability has a CVSS score of 8.4, indicating high impact on confidentiality and integrity with local privileges required. Multiple Linux kernel versions, including specific 4.15.x, 5.0.x, 5.3.x, and various 7.0.0 builds, are affected. A patch is available and included in official Linux kernel updates. No known exploits in the wild have been reported.
References
- ubuntu.com/security/CVE-2026-64151 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-64151 (opens in a new tab)
- git.kernel.org/linus/8ef3f77c440005c7f04229a75976bfc078364247 (opens in a new tab)
- ubuntu.com/security/notices/USN-8593-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8603-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8618-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8663-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8664-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8728-1 (opens in a new tab)