SB20261007197 - Use-after-free in Linux kernel smb client
Published: October 7, 2026
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Use-after-free (CVE-ID: CVE-2026-98171)
CWE-ID: CWE-416 - Use After Free
CVSSv4: 0 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N]
The vulnerability allows a remote attacker to trigger access to freed memory.
The vulnerability exists due to use-after-free in the SMB client's receive_encrypted_standard() function when handling compound encrypted frames and subsequent error paths. A remote attacker can supply compound encrypted frames that encounter an error after buffer reassignment to trigger access to freed memory.
The next_buffer pointer remains stale after its buffer is assigned to server->bigbuf.
Remediation
Install update from vendor's website.
References
- https://git.kernel.org/stable/c/05762c5bc1cfdcac36747994fde2c04387a457f1
- https://git.kernel.org/stable/c/491e33144dee872cffda207f6fcb09260728f803
- https://git.kernel.org/stable/c/72eaef1f37a3b6bec11c342736834dc3707be3e4
- https://git.kernel.org/stable/c/858d5ac22cb889266993e7670f9f0c4f4aeedd78
- https://git.kernel.org/stable/c/8749946579708ea0d339034bb7f423a67dbe89cf
- https://git.kernel.org/stable/c/96c436e4b010711452b2872558938f4ef276492a