Linux Linux Kernel
CVE-2026-64381
In the Linux kernel, the following vulnerability has been resolved: smb: client: Fix next buffer leak in receive_encrypted_standard() receive_encrypted_standard() allocates next_buffer before checking whether the number of compound PDUs already reached MAX_COMPOUND. If the limit check fails, the function returns immediately and the newly allocated next_buffer is not assigned to server->smallbuf/server->bigbuf, making it leaked. Move the MAX_COMPOUND check before allocating next_buffer.
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 only with access to the machine itself, with an ordinary user login, and without anyone at your company clicking anything.
- FIRST's prediction model gives it a 0.1% chance of attack attempts being seen in the next 30 days, ranking above 2% 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
- 7.8 (v3.1)
- Vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H- Weakness
- CWE-787
- Assigned by
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Dates
- Published
- 2026-07-25
- Last modified
- 2026-09-08
- Sources
- NVD
Affected products
- Linux Linux Kernel4.19 - 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
As listed in the NVD configuration data. Not a statement about your estate.
References
- https://git.kernel.org/stable/c/07e0ab81df1790afa35732a4e8e07ff831b29008
- https://git.kernel.org/stable/c/1c6267a1d5cf4c73b656f8181b310cbbb3e4767b
- https://git.kernel.org/stable/c/297243e365fc9fe2f8e9b7dd535a65d922cd108b
- https://git.kernel.org/stable/c/67097772df7791c53d608f04bd31c676ccf79b83
- https://git.kernel.org/stable/c/68fc0b6cc03ca58060c0f36454e169f5fe258974
- https://git.kernel.org/stable/c/9136a08dc29328edd9867f2545e73906ac9df93b
- https://git.kernel.org/stable/c/927d4805aea0a287d36dd4f826ee24d69a2afee3
- https://git.kernel.org/stable/c/94e4f672db029414b9888b5137a7559f1febf2d8