Linux Linux Kernel Improper Locking Rated 8.8 CVSS

Last refreshed2026-10-15

Status: UPDATED | Advisory ID: CVE-2026-31629

Key Details

CVE	CVE-2026-31629
CVSS Score / Version	8.8 (High) / CVSS v3.1
Updated	2026-10-15
CVSS Vector	`CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`
CVSS Prose	attack vector is adjacent; attack complexity is low; privileges required is none; user interaction is none; scope is unchanged; confidentiality impact is high; integrity impact is high; availability impact is high.
Affected products	Linux Kernel and Siemens SIMATIC S7-1500 TM MFP - GNU/Linux subsystem
Classified as	CWE-667 (Improper Locking)
Exploitation prediction (EPSS)	0.36% probability of exploitation in the next 30 days (28% percentile) -- FIRST.org's EPSS model.

Vendor	Product	Affected Versions	Patch Status
Linux	Linux Kernel
Siemens	SIMATIC S7-1500 TM MFP - GNU/Linux subsystem

Vendor

Product

Affected Versions

Patch Status

Linux

Linux Kernel

Siemens

SIMATIC S7-1500 TM MFP - GNU/Linux subsystem

Subsystems	Controllers & Field I/O, OT Supporting Infrastructure
Sectors	All Sectors

In the Linux kernel, the following vulnerability has been resolved:

nfc: llcp: add missing return after LLCP_CLOSED checks

In nfc_llcp_recv_hdlc() and nfc_llcp_recv_disc(), when the socket

state is LLCP_CLOSED, the code correctly calls release_sock() and

nfc_llcp_sock_put() but fails to return. Execution falls through to

the remainder of the function, which calls release_sock() and

nfc_llcp_sock_put() again. This results in a double release_sock()

and a refcount underflow via double nfc_llcp_sock_put(), leading to

a use-after-free.

Add the missing return statements after the LLCP_CLOSED branches

in both functions to prevent the fall-through. (NVD)

Monitor Linux's and Siemens's web pages for any future patch releases.

Source	Reference
NVD	https://nvd.nist.gov/vuln/detail/CVE-2026-31629
CVE	https://www.cve.org/CVERecord?id=CVE-2026-31629

Source

Reference

NVD

CVE