CVE-2026-23220

MEDIUM EPSS 2.0%
Published Feb 18, 20264mo ago · Modified Jun 17, 20261w ago
5.5 CVSS 3.1
Medium
Find Similar
Published Feb 18, 2026 4mo ago
Last Modified Jun 17, 2026 1w ago

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.

CVSS Details

Base Score
5.5
Exploitability
1.8
Impact
3.6
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack Vector Local
Attack Complexity Low
Privileges Required Low
User Interaction None
Scope Unchanged
Confidentiality None
Integrity None
Availability High

Threat Intelligence

EPSS Exploit Probability
2.0% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Weaknesses 1

CWE-835

Affected Products 9

VendorProductVersionRange
linuxlinux_kernel*≥5.15.145  –  <5.16
linuxlinux_kernel*≥6.1.71  –  <6.1.164
linuxlinux_kernel*≥6.6.1  –  <6.6.125
linuxlinux_kernel*≥6.7  –  <6.12.72
linuxlinux_kernel*≥6.13  –  <6.18.11
linuxlinux_kernel*≥6.19  –  <6.19.1
linuxlinux_kernel6.6any
linuxlinux_kernel6.6any
linuxlinux_kernel6.6any

References 8

  • cert-portal.siemens.com https://cert-portal.siemens.com/productcert/html/ssa-253495.html
  • git.kernel.org https://git.kernel.org/stable/c/010eb01ce23b34b50531448b0da391c7f05a72af
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/544adb0a6658ea1bff4064723761dbf05f95b1e2
  • git.kernel.org https://git.kernel.org/stable/c/5accdc5b7f28a81bbc5880ac0b8886e60c86e8c8
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/71b5e7c528315ca360a1825a4ad2f8ae48c5dc16
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/9135e791ec2709bcf0cda0335535c74762489498
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/f7b1c2f5642bbd60b1beef1f3298cbac81eb232c
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/fb3b66bd72deb5543addaefa67963b34fb163a7b
    Patch

Remediation

  • git.kernel.org https://git.kernel.org/stable/c/010eb01ce23b34b50531448b0da391c7f05a72af
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/5accdc5b7f28a81bbc5880ac0b8886e60c86e8c8
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/71b5e7c528315ca360a1825a4ad2f8ae48c5dc16
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/9135e791ec2709bcf0cda0335535c74762489498
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/f7b1c2f5642bbd60b1beef1f3298cbac81eb232c
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/fb3b66bd72deb5543addaefa67963b34fb163a7b
    Patch