Linux Linux Kernel
CVE-2026-64379
In the Linux kernel, the following vulnerability has been resolved: smb: client: mask server-provided mode to 07777 in modefromsid When modefromsid is active, parse_dacl() applies the server-provided sub_auth[2] value from the NFS mode SID to cf_mode without masking to 07777. Apply the correct masking, same as in the read path.
What this means for your business
- It affects Linux Kernel. It matters if your company, or a supplier that handles your data, runs it.
- An attacker can use it remotely, over a network, without a login, but only after tricking someone into an action such as opening a file or a link.
- FIRST's prediction model gives it a 0.3% chance of attack attempts being seen in the next 30 days, ranking above 23% of all known flaws.
What to do
- 1Check whether your company or your suppliers run Linux Kernel, and which version. The affected versions are listed further down this page.
- 2If you do, apply the vendor's fix. A patch or vendor advisory has been published.
Fastnexa security experts
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Scoring
- CVSS
- 7.1 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H- Assigned by
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Dates
- Published
- 2026-07-25
- Last modified
- 2026-09-08
- Sources
- NVD
Affected products
- Linux Linux Kernel5.4 - 5.10.261, 5.11 - 5.15.212, 5.16 - 6.1.178, 6.2 - 6.6.145, 6.7 - 6.12.96, 6.13 - 6.18.39, 6.19 - 7.1.4, 7.2
As listed in the NVD configuration data. Not a statement about your estate.
References
- https://git.kernel.org/stable/c/08c600b7e1818539ba5efee4cdb06215c245ca78
- https://git.kernel.org/stable/c/5f6f2241034f189c69d4d0b5f8fe24a0c25b0c14
- https://git.kernel.org/stable/c/b84e002e0df26bbc6cbd3ca01b8212601fe0ae7d
- https://git.kernel.org/stable/c/c6c484a7d5bff6b929a86d7ed5130f29834c6a0d
- https://git.kernel.org/stable/c/e3d9c7160d483fc8f9e225aafad8ecbbc43f3151
- https://git.kernel.org/stable/c/ee2216dbdf0c677e89bb43e03247dba590ed00ef
- https://git.kernel.org/stable/c/f511807feee7cb29b61bdfa86472c7e9e2e5df94
- https://git.kernel.org/stable/c/f80add1bfb3425100a325b14f19648e75669a954