CVE-2026-68457: Linux kernel · ksmbd: use opener credentials for FSCTL mutations SET_SPARSE, SET_ZERO_DATA and
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 9.1 Critical · fixed in 6.8.0-147.147 : patch Linux kernel as a priority.
Data as of 28 Oct 2026, 05:11 UTC
- EPSS
- 0.7% chance of exploitation in 30 days – higher than 53% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 6.8.0-147.147, 6.8.0-1067.70, 7.0.0-1013.13~24.04.1 +27
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 15 Aug 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
Upgrade to a fixed release listed under Affected software.
Patches and advisories
- ubuntu.com/security/notices/USN-8781-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8816-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8816-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8816-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-8816-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-8888-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8888-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8917-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8918-1 (opens in a new tab)
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 patch is available and should be applied. Fixed Linux kernel versions include 6.8.0-147.147, 6.8.0-1067.70, 7.0.0-1013.13~24.04.1, 6.8.0-1071.79, 7.0.0-1017.17~24.04.1, among others. Users should upgrade to these fixed versions to remediate the vulnerability. No alternative mitigations or workarounds are indicated by the vendor advisory.
Description
A critical vulnerability in the Linux kernel's ksmbd component was fixed, addressing improper use of credentials during certain FSCTL mutations (SET_SPARSE, SET_ZERO_DATA, SET_COMPRESSION). The flaw involved using the current worker credentials instead of the opener's credentials when performing file system operations, potentially allowing unauthorized inode attribute changes. This issue affects multiple Linux kernel versions prior to fixed releases and has a CVSS score of 9.1.
References
- ubuntu.com/security/CVE-2026-68457 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-68457 (opens in a new tab)
- git.kernel.org/linus/c6394bcaf254c5baf9aff43376020be5db6d3316 (opens in a new tab)
- git.kernel.org/stable/c/1e112c47ec5dd1942e2d4ca6e8e9b712238e20c2 (opens in a new tab)
- git.kernel.org/stable/c/a8c18434e1f0d9f7989170bdb0490c0160baf065 (opens in a new tab)
- git.kernel.org/stable/c/c6394bcaf254c5baf9aff43376020be5db6d3316 (opens in a new tab)
- git.kernel.org/stable/c/cfb2c6f71d61ed807c9d7a7af331d406f1f31877 (opens in a new tab)
- git.kernel.org/stable/c/e205f3e7e8c31a47cd11efb6cf663a527177e432 (opens in a new tab)
- git.kernel.org/stable/c/fb1cae6302d58414ddf029e3f642711bd30243f7 (opens in a new tab)
- ubuntu.com/security/notices/USN-8781-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8816-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8816-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8816-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-8816-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-8888-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8888-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8917-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8918-1 (opens in a new tab)