CVE-2026-93811: Linux kernel · ksmbd: Fix acl.sd_buf memory leak and invalid sd_size error handling 1.
Affects Linux kernelSource GCVE Database
Not known to be exploited.
Data as of 26 Oct 2026, 17:16 UTC
Rated by Threat Radar · CVSS not yet scored by NVD
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 6% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Exploitation 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 has been applied to the Linux kernel to address this issue by correcting the error handling and memory freeing logic in ksmbd. Users should update to a kernel version that includes this fix. Patch status is confirmed by the description of the resolved vulnerability. No additional mitigation steps are indicated.
Description
A memory leak and improper error handling vulnerability in the Linux kernel's ksmbd component was fixed. The issue involved failure to free the acl.sd_buf buffer on certain error paths in the ndr_decode_v4_ntacl() function, leading to memory leaks and stale pointers. The fix ensures that acl.sd_buf is freed on all error paths and that appropriate error codes are returned.
References
- ubuntu.com/security/CVE-2026-93811 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-93811 (opens in a new tab)
- git.kernel.org/stable/c/c3836f55e0dab96314774215e12d87f63fa919f2 (opens in a new tab)
- git.kernel.org/stable/c/d708a36634bb7b6f94d0e76d587d2ec50b2b93b5 (opens in a new tab)
- git.kernel.org/stable/c/6e6329322ad733c5b23555c609353841560b26bc (opens in a new tab)
- nvd.nist.gov/vuln/detail/CVE-2026-93811 (opens in a new tab)
- git.kernel.org/stable/c/86c2625fb9863139b359805fc6be1e31edbd3d65 (opens in a new tab)
- git.kernel.org/stable/c/edc17db83085624a2b1bacf6a4521d7f15571737 (opens in a new tab)
- git.kernel.org/stable/c/f46a70a082bdbfecbe074af8a719c26c4deb58c6 (opens in a new tab)