CVE-2026-31629
Published: May 3, 2026Last modified: May 3, 2026
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.
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 8.8 |
| Attack Vector | ADJACENT_NETWORK |
| Attack complexity | LOW |
| Privileges required | NONE |
| User interaction | NONE |
| Scope | UNCHANGED |
| Confidentiality | HIGH |
| Integrity impact | HIGH |
| Availability impact | HIGH |
| Vector | CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
Status
| Product | Release | Package | Status |
|---|---|---|---|
| Alpaquita Linux | 23 LTS | linux-lts | Vulnerable (6.1.170-r0) |
| 25 LTS | linux-lts | Fixed (6.12.85-r0) | |
| Stream | linux-lts | Fixed (6.12.85-r0) |
References
- https://git.kernel.org/stable/c/0eb1263a3b8c36418c9ba295c9ab3abed664edbf
- https://git.kernel.org/stable/c/2b5dd4632966c39da6ba74dbc8689b309065e82c
- https://git.kernel.org/stable/c/796e0cac058252d0ad34ebe288e6f7979b5fc9b2
- https://git.kernel.org/stable/c/8977fad2b3c6eefd414131168d597c5d1d5e1abf
- https://git.kernel.org/stable/c/aba4712e8f0381cd5d196534ce2ad082626a5ab6
- https://git.kernel.org/stable/c/ff3d9e8f7244293e303f7b6ef70774291c7c27e9