CVE-2026-90104: Linux kernel · NFSv4.1: zero referring call lists before decoding
Affects Linux kernelSource CVE Database V5
Not known to be exploited · CVSS 9.8 Critical · fixed in f31f3c042e024aef437cda42f0424ae8d4594b6c : patch Linux kernel as a priority.
Data as of 26 Oct 2026, 12:55 UTC
- EPSS
- 0.6% chance of exploitation in 30 days – higher than 50% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in f31f3c042e024aef437cda42f0424ae8d4594b6c, f4d23937e1c41995c2f54af26c89b5e48a41c299, ed54460caf5b5aa65ec03c9a6032d831f39f19f5 +2
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 17 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
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in– |
Description
In the Linux kernel, the following vulnerability has been resolved: NFSv4.1: zero referring call lists before decoding decode_cb_sequence_args() allocates csa_rclists with kmalloc_objs(), so each referring_call_list starts uninitialized. decode_rc_list() assigns rcl_refcalls only when rcl_nrefcalls is nonzero. A valid list with zero referring calls therefore leaves the pointer uninitialized, and nfs4_callback_sequence() later passes stale slab contents to kfree(). Allocate csa_rclists with kzalloc_objs() so every rcl_refcalls member is NULL from the beginning, including valid empty referring call lists.
References
- git.kernel.org/stable/c/ed54460caf5b5aa65ec03c9a6032d831f39f19f5 (opens in a new tab)
- git.kernel.org/stable/c/7510a5b9edec9d9536a4e69f10edfb2592e6cf7f (opens in a new tab)
- git.kernel.org/stable/c/f4d23937e1c41995c2f54af26c89b5e48a41c299 (opens in a new tab)
- git.kernel.org/stable/c/f31f3c042e024aef437cda42f0424ae8d4594b6c (opens in a new tab)
- git.kernel.org/stable/c/8fa4804fe62ca4155a2d8fc2789d630376cbf2fc (opens in a new tab)