CVE-2026-89502: Linux kernel · ring-buffer: Free cpu_buffer::free_page with subbuf_order
Affects Linux kernelSource GCVE Database
Not known to be exploited.
Data as of 26 Oct 2026, 12:55 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 to correctly free cpu_buffer::free_page using the appropriate subbuf_order. Users should apply the official kernel updates for the affected linux-hwe-edge versions to remediate this vulnerability.
Description
A vulnerability in the Linux kernel's ring-buffer implementation related to the freeing of cpu_buffer::free_page with subbuf_order has been resolved. The issue occurs when sub-buffers use an order greater than 0, causing cpu_buffer->free_page to be allocated incorrectly. This vulnerability affects specific versions of the linux-hwe-edge kernel and has been assigned a medium severity rating.
References
- nvd.nist.gov/vuln/detail/CVE-2026-89502 (opens in a new tab)
- git.kernel.org/stable/c/234b1a72e9706fe20c08c96f4374ec8e83b934cb (opens in a new tab)
- git.kernel.org/stable/c/77275ccea06eaf297e8e6ac3fc830cb72086379a (opens in a new tab)
- git.kernel.org/stable/c/81063bbb16c4fcf0136c9117d5e49d3621dd6a1e (opens in a new tab)
- git.kernel.org/stable/c/8c1ecdcdea738efe0494af908f12c0ae3a97fffa (opens in a new tab)
- ubuntu.com/security/CVE-2026-89502 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-89502 (opens in a new tab)
- git.kernel.org/linus/234b1a72e9706fe20c08c96f4374ec8e83b934cb (opens in a new tab)