Improper access control in Linux kernel - CVE-2026-64137
Published: July 20, 2026
Vulnerability identifier: #VU138500
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2026-64137
CWE-ID: CWE-284
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vendor: Linux Foundation
Affected software:
Linux kernel
Linux kernel
Detailed vulnerability description
The vulnerability allows a local user to disclose sensitive information.
The vulnerability exists due to improper access control in the CIFS SWN generic netlink multicast group when joining the multicast group and receiving registration messages. A local user can join the CIFS_GENL_MCGRP_SWN group to disclose sensitive information.
For NTLM-authenticated mounts, exposed registration messages may include the username, domain, and password attributes copied from the CIFS session.
How to mitigate CVE-2026-64137
Install security update from vendor's repository.
Sources
- https://git.kernel.org/stable/c/969bc6370334a5b4720c5470783295d6484bbc95
- https://git.kernel.org/stable/c/9919021a3b7974ae66a5f9915e3a48c10cfd409b
- https://git.kernel.org/stable/c/9cf7eb8919344932f909b2fac76296f7656fda8d
- https://git.kernel.org/stable/c/a3238b09c58f323e40743ce174cd0ab81b5c09ed
- https://git.kernel.org/stable/c/a8d17d22db591099519a89f14dd24810daba74c3
- https://git.kernel.org/stable/c/c2397b93fbb6f44a788fff30f99be2c20cc5e50f
- https://git.kernel.org/stable/c/d1ebfce2c1d161186a82e77590bf7da2ea1bce91