Use-after-free in Linux kernel - CVE-2026-98261
Published: October 8, 2026
Vulnerability identifier: #VU153957
CSH Severity: High
CVSS v4: 9.2 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-98261
CWE-ID: CWE-416
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to compromise system confidentiality, integrity, and availability.
The vulnerability exists due to use-after-free in cifs_chan_skip_or_disable() when handling a secondary channel that is no longer supported by the server. A remote attacker can trigger the release of a channel reference followed by access to freed server objects to compromise system confidentiality, integrity, and availability.
Both the secondary channel and its primary server can be freed if cifs_put_tcp_session() drops their last references.
Affected software
Linux kernel
How to mitigate CVE-2026-98261
Install security update from vendor's repository.
Linux kernel - update to 7.0 rc3
External References
- https://git.kernel.org/stable/c/0338489960ddad6368bce55e8adbc176c523093d
- https://git.kernel.org/stable/c/717e0a25036b6c92cecace30913b2d874a4c22b8
- https://git.kernel.org/stable/c/7a1b27780b113583a94256d58dabfe7c0d9286e7
- https://git.kernel.org/stable/c/edd52eae5fcfb8433b6bb0e7cd98db438fe01227
- https://git.kernel.org/stable/c/fcc0a935bb6e37ecbf7e4335061309f896f35780