Junglewise Threat Intelligence

CVE-2026-31629: Linux Kernel use-after-free in NFC LLCP component

CVE-2026-31629 · Severity: high · CVSS 8.8 · Published 2026-04-24

Technologies: Linux Kernel. Vendors: Linux.

Executive brief

A vulnerability exists in the Linux kernel's Near Field Communication (NFC) component. An attacker within physical proximity of a device could potentially trigger a system crash or execute unauthorized code by sending specially crafted NFC signals. This could lead to a complete loss of device availability or the exposure of sensitive data stored on the system.

Technical details

A use-after-free vulnerability exists in the Linux kernel NFC LLCP implementation due to missing return statements in nfc_llcp_recv_hdlc() and nfc_llcp_recv_disc(). When a socket is in the LLCP_CLOSED state, the code performs cleanup but fails to exit, leading to a fall-through that triggers a double release_sock() and a reference count underflow via a second nfc_llcp_sock_put(). This flaw can be triggered by an adjacent attacker via the NFC protocol. Patches have been released across multiple stable kernel branches to add the missing return statements.

Affected products

  • Linux Linux Kernel 3.3 to 6.6.136, 6.7 to 6.12.83, 6.13 to 6.18.24, 6.19 to 6.19.14, 7.0 to 7.0.1

Timeline

  • 2026-04-08: other: Patch authored
  • 2026-04-24: disclosed: Initial disclosure from kernel.org
  • 2026-04-24: advisory: NVD publication date

References

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