CVE-2026-31629

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 v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector ADJACENT_NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/0eb1263a3b8c36418c9ba295c9ab3abed664edbf	Patch
https://git.kernel.org/stable/c/2b5dd4632966c39da6ba74dbc8689b309065e82c	Patch
https://git.kernel.org/stable/c/665315df9c3486cb213fc44d83cc8bcd47fe0d26
https://git.kernel.org/stable/c/796e0cac058252d0ad34ebe288e6f7979b5fc9b2	Patch
https://git.kernel.org/stable/c/8977fad2b3c6eefd414131168d597c5d1d5e1abf	Patch
https://git.kernel.org/stable/c/9b49e2a4b8219a2fc5cebf94f4ec34e509aff8a6
https://git.kernel.org/stable/c/aba4712e8f0381cd5d196534ce2ad082626a5ab6	Patch
https://git.kernel.org/stable/c/b2a23529593d011fb433a3d711fc597ed6a6bd2f
https://git.kernel.org/stable/c/ff3d9e8f7244293e303f7b6ef70774291c7c27e9	Patch

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::

History

No history.

Information

Published : 2026-04-24 15:16

Updated : 2026-06-17 10:34

NVD link : CVE-2026-31629

Mitre link : CVE-2026-31629

CVE.ORG link : CVE-2026-31629

JSON object : View

Products Affected

linux

linux_kernel

CWE

CWE-667

Improper Locking

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"source": "nvd@nist.gov", "description": [{"lang": "en", "value": "CWE-667"}]}], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnfc: llcp: add missing return after LLCP_CLOSED checks\n\nIn nfc_llcp_recv_hdlc() and nfc_llcp_recv_disc(), when the socket\nstate is LLCP_CLOSED, the code correctly calls release_sock() and\nnfc_llcp_sock_put() but fails to return. Execution falls through to\nthe remainder of the function, which calls release_sock() and\nnfc_llcp_sock_put() again. This results in a double release_sock()\nand a refcount underflow via double nfc_llcp_sock_put(), leading to\na use-after-free.\n\nAdd the missing return statements after the LLCP_CLOSED branches\nin both functions to prevent the fall-through."}], "lastModified": "2026-06-17T10:34:07.460", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "FAB12062-558C-4570-A908-D71195858ADA", "versionEndExcluding": "6.6.136", "versionStartIncluding": "3.3"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "7F0AE5B5-23AC-4DCC-B37A-51CA1DAE7BA8", "versionEndExcluding": "6.12.83", "versionStartIncluding": "6.7"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "8126B8B8-6D0B-4443-86C1-672AEE893555", "versionEndExcluding": "6.18.24", "versionStartIncluding": "6.13"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "D6A8A074-BBF4-4803-ABED-519A839435BB", "versionEndExcluding": "6.19.14", "versionStartIncluding": "6.19"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "9B5888AB-7403-4335-89E4-21CC0B48366A", "versionEndExcluding": "7.0.1", "versionStartIncluding": "7.0"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}