CVE-2026-89636: Linux kernel · smb: client: clear ce->tgthint in free_tgts()
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 9.8 Critical.
Data as of 26 Oct 2026, 17:16 UTC
- EPSS
- 0.6% chance of exploitation in 30 days – higher than 51% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HExploitation 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 is available that sets ce->tgthint to NULL in free_tgts() after freeing the target structures. Users should apply the official kernel updates that include this patch to remediate the vulnerability.
Description
A use-after-free vulnerability in the Linux kernel's SMB client was resolved by clearing a dangling pointer after freeing target structures. The flaw occurs when free_tgts() frees all structures in ce->tlist but leaves ce->tgthint pointing to freed memory, potentially leading to memory corruption if used later.
References
- nvd.nist.gov/vuln/detail/CVE-2026-89636 (opens in a new tab)
- git.kernel.org/stable/c/5baab40404a9393bcc0b7b8f1950bf2c307e0984 (opens in a new tab)
- git.kernel.org/stable/c/7507bd1885643d0461a6017767492450af1ce2a3 (opens in a new tab)
- git.kernel.org/stable/c/9ab46a13798a61d9d020b01d4e57efdabe6624fa (opens in a new tab)
- git.kernel.org/stable/c/b1b741cf8e7ce1b91d937e23decd3d3358748700 (opens in a new tab)
- ubuntu.com/security/CVE-2026-89636 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-89636 (opens in a new tab)
- git.kernel.org/linus/b1b741cf8e7ce1b91d937e23decd3d3358748700 (opens in a new tab)