CVE-2026-97421: Linux kernel · RDMA/umem: Be careful about boundary conditions in ib_umem_find_best_pgsz()
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.8 High.
Data as of 26 Oct 2026, 17:16 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 2% 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 24 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 for this vulnerability has been implemented in the Linux kernel. Users and administrators should apply the official kernel updates that address these boundary condition checks in ib_umem_find_best_pgsz(). Since this is a kernel-level issue, upgrading to a patched kernel version is the recommended remediation.
Description
A vulnerability in the Linux kernel's RDMA umem subsystem was resolved, addressing boundary condition issues in the ib_umem_find_best_pgsz() function. The flaw involved improper handling of 64-bit I/O virtual addresses (iova) and length checks, which could lead to truncation and overflow errors, particularly on 32-bit systems.
References
- ubuntu.com/security/CVE-2026-97421 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-97421 (opens in a new tab)
- git.kernel.org/stable/c/5fc5b73109540809b094710fac44da81dd8a3ff8 (opens in a new tab)
- git.kernel.org/stable/c/09ea6837a0434fb4db99528a5055b6d822135dcf (opens in a new tab)
- git.kernel.org/stable/c/ae3cf7d2c4d506c5c91746321644e1a08d989e2a (opens in a new tab)
- nvd.nist.gov/vuln/detail/CVE-2026-97421 (opens in a new tab)
- git.kernel.org/stable/c/3014da7587ce006cd08004fd6b257626b314e0a3 (opens in a new tab)
- git.kernel.org/stable/c/ddccf6cc3861de2fe60986933bead79220e0d797 (opens in a new tab)
- git.kernel.org/stable/c/e9bbb5f5349ef560ff6f0395564f04c3aa664559 (opens in a new tab)