IM
IronMonkey Threat Research

CVE-2026-31629 HIGH

Published: 2026-04-24 | Last Modified: 2026-06-01 | Status: Modified

Description

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.

CVSS Metrics

Base Score: 8.8 (HIGH)

CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Attack VectorADJACENT_NETWORK
Attack ComplexityLOW
Privileges RequiredNONE
User InteractionNONE
ScopeUNCHANGED
Confidentiality ImpactHIGH
Integrity ImpactHIGH
Availability ImpactHIGH

Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67

Type: Secondary

Exploitability Score: 2.8

Impact Score: 5.9

Weaknesses

Source Type Description
[email protected] Primary
en CWE-667

Affected Products

Vendor Product Version Update Type
linux linux_kernel * <built-in method update of dict object at 0x7fd370038680> Operating System
linux linux_kernel * <built-in method update of dict object at 0x7fd368531640> Operating System
linux linux_kernel * <built-in method update of dict object at 0x7fd369ad5100> Operating System
linux linux_kernel * <built-in method update of dict object at 0x7fd31b20e100> Operating System
linux linux_kernel * <built-in method update of dict object at 0x7fd370038800> Operating System

Affected Configurations

Operator: OR

Vulnerable CPE
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

References