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.
Affected products
linux: linux kernel
References10
- git.kernel.org/stable/c/0eb1263a3b8c36418c9ba295c9ab3abed664edbf Patch
- git.kernel.org/stable/c/2b5dd4632966c39da6ba74dbc8689b309065e82c Patch
- git.kernel.org/stable/c/796e0cac058252d0ad34ebe288e6f7979b5fc9b2 Patch
- git.kernel.org/stable/c/8977fad2b3c6eefd414131168d597c5d1d5e1abf Patch
- git.kernel.org/stable/c/aba4712e8f0381cd5d196534ce2ad082626a5ab6 Patch
- git.kernel.org/stable/c/ff3d9e8f7244293e303f7b6ef70774291c7c27e9 Patch
- git.kernel.org/stable/c/665315df9c3486cb213fc44d83cc8bcd47fe0d26
- git.kernel.org/stable/c/9b49e2a4b8219a2fc5cebf94f4ec34e509aff8a6
- git.kernel.org/stable/c/b2a23529593d011fb433a3d711fc597ed6a6bd2f
- cert-portal.siemens.com/productcert/html/ssa-784472.html
Metrics
- CVSS 3.1
-
8.8
HIGH
Score source: CNA
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 17 · as of 13 November 2026
- CWE
- CWE-667
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