CVE-2026-89439: Linux kernel · platform/x86: ISST: Add a NULL check for sst_inst[]
Affects Linux kernelSource GCVE Database
Not known to be exploited.
Data as of 26 Oct 2026, 13:47 UTC
Rated by Threat Radar · CVSS not yet scored by NVD
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 10% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Exploitation 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 to add the necessary NULL check. Users should update to the fixed kernel version once available. No additional mitigation steps are indicated.
Description
In the Linux kernel, the following vulnerability has been resolved: platform/x86: ISST: Add a NULL check for sst_inst[] To be consistent with other places, add a NULL check for failed socket loading by checking isst_common.sst_inst[].
References
- nvd.nist.gov/vuln/detail/CVE-2026-89439 (opens in a new tab)
- git.kernel.org/stable/c/3de2776e9d7073765c10c2326c2bda5926811ea6 (opens in a new tab)
- git.kernel.org/stable/c/49a95fe1f64f41c2e8959e525aefdb10f23b293e (opens in a new tab)
- git.kernel.org/stable/c/c280fcd53b938b70c7dee9ce1a66b32bd6e5ebaa (opens in a new tab)
- git.kernel.org/stable/c/ef7975af15126dd70ace519da7bb33f2848b9064 (opens in a new tab)
- msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-89439.json (opens in a new tab)
- support.microsoft.com/lifecycle (opens in a new tab)
- first.org/cvss (opens in a new tab)
- ubuntu.com/security/CVE-2026-89439 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-89439 (opens in a new tab)
- git.kernel.org/linus/3de2776e9d7073765c10c2326c2bda5926811ea6 (opens in a new tab)