CVE-2026-23220

MEDIUM

Linux Kernel - DoS

Title source: llm
STIX 2.1

Description

In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix infinite loop caused by next_smb2_rcv_hdr_off reset in error paths The problem occurs when a signed request fails smb2 signature verification check. In __process_request(), if check_sign_req() returns an error, set_smb2_rsp_status(work, STATUS_ACCESS_DENIED) is called. set_smb2_rsp_status() set work->next_smb2_rcv_hdr_off as zero. By resetting next_smb2_rcv_hdr_off to zero, the pointer to the next command in the chain is lost. Consequently, is_chained_smb2_message() continues to point to the same request header instead of advancing. If the header's NextCommand field is non-zero, the function returns true, causing __handle_ksmbd_work() to repeatedly process the same failed request in an infinite loop. This results in the kernel log being flooded with "bad smb2 signature" messages and high CPU usage. This patch fixes the issue by changing the return value from SERVER_HANDLER_CONTINUE to SERVER_HANDLER_ABORT. This ensures that the processing loop terminates immediately rather than attempting to continue from an invalidated offset.

Scores

CVSS v3 5.5
EPSS 0.0003
EPSS Percentile 7.1%
Attack Vector LOCAL
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Details

CWE
CWE-835
Status published
Products (25)
linux/Kernel < 6.1.164linux
linux/Kernel 6.13.0 - 6.19.1linux
linux/Kernel 6.2.0 - 6.6.125linux
linux/Kernel 6.6.0 - 6.12.72linux
linux/Kernel 6.7.0 - 6.18.11linux
Linux/Linux < 6.6
Linux/Linux 4b9b7ea1ffb1e34f01fa5726d0c184931b9ba565
Linux/Linux 4b9b7ea1ffb1e34f01fa5726d0c184931b9ba565 - 544adb0a6658ea1bff4064723761dbf05f95b1e2
Linux/Linux 5.15.203 - 5.15.*
Linux/Linux 6.1.164 - 6.1.*
... and 15 more
Published Feb 18, 2026
Tracked Since Feb 18, 2026