CVE-2026-98870: Linux kernel · ksmbd: remove stale channels from all sessions on teardown
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 8.8 High.
Data as of 28 Oct 2026, 02:14 UTC
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 23 Oct 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 24.04 LTSlinux-aws-6.14pkg:deb/ubuntu/linux-aws-6.14?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSlinux-aws-6.17pkg:deb/ubuntu/linux-aws-6.17?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSlinux-azure-6.11pkg:deb/ubuntu/linux-azure-6.11?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSlinux-azure-6.14pkg:deb/ubuntu/linux-azure-6.14?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSlinux-azure-6.17pkg:deb/ubuntu/linux-azure-6.17?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSlinux-azure-fde-6.14pkg:deb/ubuntu/linux-azure-fde-6.14?arch=source&distro=nobleOther 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 is available that removes the conn->binding conditional check in ksmbd_sessions_deregister(), ensuring stale channels are always removed from all sessions on teardown. Users should apply the updated Linux kernel versions that include this fix. No additional mitigations are specified or required.
Description
CVE-2026-98870 is a high severity use-after-free vulnerability in the Linux kernel's ksmbd component. It occurs because stale channels are not properly removed from all sessions on connection teardown, leading to dereferencing freed memory and leaking sessions. This flaw affects multiple specific Linux kernel versions. The vulnerability has a CVSS score of 8.8, indicating critical confidentiality, integrity, and availability impacts. A fix is available that removes the conditional gate so that all stale channels are always removed on teardown.
References
- ubuntu.com/security/CVE-2026-98870 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-98870 (opens in a new tab)
- git.kernel.org/stable/c/9cd6d714d3ca0cff296542dc989696884e41970f (opens in a new tab)
- git.kernel.org/stable/c/a15cae16f4432a5ad919ee633e31b07178492955 (opens in a new tab)
- git.kernel.org/stable/c/b10665730fbf6b5e45fe422badcbbc3f0df96ef5 (opens in a new tab)
- git.kernel.org/stable/c/b145f9b56c87f9c23ad5464ab0844dbc1de12b36 (opens in a new tab)
- git.kernel.org/stable/c/f8200bb4994e65a2e5c5b314789eeae39078619d (opens in a new tab)