# CVE-2026-31629

> Vulnerability · severity: **HIGH** (CVSS 8.8).

## 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.

## Key facts

- **CVE ID:** CVE-2026-31629
- **Published:** 2026-04-24
- **CVSS severity:** HIGH
- **CVSS base score:** 8.8
- **CWE codes:** CWE-667

## Affected products

- `linux:linux_kernel`

## Primary sources

- NIST NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-31629

## Citation

> AI Analytics. CVE-2026-31629. Retrieved 2026-08-02 from https://api.ai-analytics.org/cve/CVE-2026-31629. Derived from NIST NVD. Licensed CC0.

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