PT-2026-30577 · Linux · Linux Kernel

Published 2026-04-06 · Updated 2026-05-26 · CVE-2026-31409

Positive Technologies (AI Summary)

CVSS v3.1

8.8

High

Base vector

AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)

Description The Linux kernel contains a flaw within the ksmbd module. Specifically, when a multichannel SMB2 SESSION SETUP request with SMB2 SESSION REQ FLAG BINDING fails, the conn->binding flag is incorrectly set to true and not cleared in the error path. This results in the connection remaining in a binding state, causing subsequent ksmbd session lookup all() calls to default to the global sessions table.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Weakness Enumeration

CWE-390

Related Identifiers

BDU:2026-04926

CVE-2026-31409

ECHO-DFCD-C174-2B88

Affected Products

Linux Kernel

References · 24

• https://git.kernel.org/stable/c/282343cf8a4a5a3603b1cb0e17a7083e4a593b03 · Patch
• https://osv.dev/vulnerability/ROOT-OS-UBUNTU-2204-CVE-2026-31409 · Vendor Advisory
• https://git.kernel.org/stable/c/6260fc85ed1298a71d24a75d01f8b2e56d489a60 · Patch
• https://git.kernel.org/stable/c/6ebef4a220a1ebe345de899ebb9ae394206fe921 · Patch
• https://git.kernel.org/stable/c/9feb2d1bf86d9e5e66b8565f37f8d3a7d281a772 · Patch
• https://git.kernel.org/stable/c/d073870dab8f6dadced81d13d273ff0b21cb7f4e · Patch
• https://cve.org/CVERecord?id=CVE-2026-31409 · Security Note
• https://git.kernel.org/stable/c/89afe5e2dbea6e9d8e5f11324149d06fa3a4efca · Patch
• https://osv.dev/vulnerability/DEBIAN-CVE-2026-31409 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-31409 · Security Note
• https://bdu.fstec.ru/vul/2026-04926 · Security Note
• https://security-tracker.debian.org/tracker/CVE-2026-31409 · Vendor Advisory
• https://osv.dev/vulnerability/BELL-CVE-2026-31409 · Vendor Advisory
• https://ubuntu.com/security/CVE-2026-31409 · Vendor Advisory
• https://osv.dev/vulnerability/UBUNTU-CVE-2026-31409 · Vendor Advisory