CVE-2025-22037: Linux kernel · ksmbd: fix null pointer dereference in alloc_preauth_hash()
Affects Linux kernelSource GCVE Database
Not known to be exploited · 69% EPSS · CVSS 7.5 High · fixed in 6.8.0-1047.50~22.04.1 : patch Linux kernel as a priority.
Data as of 26 Oct 2026, 11:42 UTC
- EPSS
- 69.5% chance of exploitation in 30 days – higher than 99% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 6.8.0-1047.50~22.04.1, 6.8.0-1051.57~22.04.1, 6.8.0-1048.51~22.04.1 +30
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 16 Apr 2025
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.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 25.10linux-azure-fdepkg:deb/ubuntu/linux-azure-fde@6.17.0-1017.17?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSlinuxpkg:deb/ubuntu/linux@6.8.0-101.101?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTSlinux-awspkg:deb/ubuntu/linux-aws@6.8.0-1047.50?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure@6.8.0-1051.57?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTSlinux-azure-6.11pkg:deb/ubuntu/linux-azure-6.11@6.11.0-1018.18~24.04.1?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTSlinux-azure-fdepkg:deb/ubuntu/linux-azure-fde@6.8.0-1061.68?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
An official patch is available and should be applied to affected Linux kernel versions. The Ubuntu security advisory USN-7594-1 confirms the fix is included in updated kernel packages. Users should update their Linux kernel to the fixed versions as soon as possible to mitigate this issue.
Description
A null pointer dereference vulnerability in the Linux kernel's ksmbd component was fixed. The flaw allowed a client sending a malformed SMB2 negotiate request to cause ksmbd to return an error but still accept an SMB2 session setup request without proper preauthentication info allocated. The patch introduces a connection status check to ignore session setup requests if the negotiate phase is incomplete. This vulnerability has a CVSS score of 7.5 and is considered medium severity. Multiple specific Linux kernel versions are affected. An official patch is available as detailed in the Ubuntu security advisory USN-7594-1.
References
- ubuntu.com/security/CVE-2025-22037 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2025-22037 (opens in a new tab)
- git.kernel.org/linus/c8b5b7c5da7d0c31c9b7190b4a7bba5281fc4780 (opens in a new tab)
- git.kernel.org/stable/c/8f216b33a5e1b3489c073b1ea1b3d7cb63c8dc4d (opens in a new tab)
- git.kernel.org/stable/c/b8eb243e670ecf30e91524dd12f7260dac07d335 (opens in a new tab)
- git.kernel.org/stable/c/c8b5b7c5da7d0c31c9b7190b4a7bba5281fc4780 (opens in a new tab)
- git.kernel.org/stable/c/ca8bed31edf728a662ef9d6f39f50e7a7dc2b5ad (opens in a new tab)
- ubuntu.com/security/notices/USN-7594-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7594-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7605-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7606-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7605-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7594-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-7628-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8059-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8059-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8059-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-8059-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-8059-5 (opens in a new tab)
- ubuntu.com/security/notices/USN-8059-6 (opens in a new tab)