CVE-2026-89794: Linux kernel · ksmbd: zero pipe read compound padding
Source GCVE Database
Not known to be exploited · fixed in f188a400dd5285fec5a84548fe8dca49eee01155 : update Linux kernel when convenient.
Data as of 30 Oct 2026, 19:33 UTC
Rated Medium by Threat Radar's AI analysis · CVSS not yet scored by NVD
Thin evidence
One scorer or none- Patch
- Available – fixed in f188a400dd5285fec5a84548fe8dca49eee01155, d83a9de7cecd401c3d3e00ed6371194dcd7313e4, c7516bdf7d2c1a64b14a9f444e2ee58c12c384ae +5
Exploitation evidence
Disclosed: evidence found.
CVE published 16 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: 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 30 Oct 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in– |
AI-suggested
A fix for this vulnerability has been implemented in the Linux kernel by adjusting memory allocation and clearing unused padding bytes. Users should apply the official kernel updates that include this fix.
Description
CVE-2026-89794 is a vulnerability in the Linux kernel's ksmbd component related to zero pipe read compound padding. The issue arises because smb2_read_pipe() allocates only the payload size without accounting for alignment padding, potentially exposing up to seven bytes of uninitialized kernel heap memory. The vulnerability has been resolved by allocating the aligned size and clearing the unused tail before pinning the response buffer.
References
- nvd.nist.gov/vuln/detail/CVE-2026-89794 (opens in a new tab)
- git.kernel.org/stable/c/134d980491b435e5cdb3171225e2506ff17867d1 (opens in a new tab)
- git.kernel.org/stable/c/73f860489e3be2245598d1819226304fc5b87291 (opens in a new tab)
- git.kernel.org/stable/c/be15b8da4a82cf1e1f9880b2661b90770606eec1 (opens in a new tab)
- git.kernel.org/stable/c/c7516bdf7d2c1a64b14a9f444e2ee58c12c384ae (opens in a new tab)
- git.kernel.org/stable/c/d83a9de7cecd401c3d3e00ed6371194dcd7313e4 (opens in a new tab)
- git.kernel.org/stable/c/f188a400dd5285fec5a84548fe8dca49eee01155 (opens in a new tab)