CVE-2026-31629: nfc: llcp: add missing return after LLCP_CLOSED checks
Vulnerability summary
CVE-2026-31629 is a high (CVSS 8.8) Improper Locking vulnerability in linux. EPSS estimates a 0.25% chance of exploitation in the next 30 days, higher than 16.7% of scored vulnerabilities.
Not severe (CVSS 8.8, adjacent network); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 177 · Related 178Showing 100 of 178.
Timeline
- 24-04-2026PublishedVulnerability first disclosed.
- 15-10-2026Last modifiedVulnerability information updated.
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.
CVSS metrics
5 scores · 5 sources · 1 version- OSV · UbuntuEcosystem advisory · calculated8.8HighCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- OSV · DebianEcosystem advisory · calculated8.8HighCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- OSV · ChainguardEcosystem advisory · calculated8.8HighCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- NVDNIST8.8HighCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS trend
Probability
0.25%
Chance of exploitation in the next 30 days
Percentile
17%
Versus all other CVEs
30-day change
Decrease -0.10 pp
From 0.35% on 04-10-2026
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Known conditions: adjacent network, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.
Ubuntu158 products
- linuxAll versions (No fix recorded) | < 5.15.0-186.196 | < 6.8.0-136.136 | < 7.0.0-27.27
- linux-allwinner-5.19All versions (No fix recorded)
- linux-awsAll versions (No fix recorded) | < 5.15.0-1112.119 | < 6.8.0-1061.64 | < 7.0.0-1008.8
- linux-aws-5.0All versions (No fix recorded)
- linux-aws-5.11All versions (No fix recorded)
Chainguard10 products
- linux-aws-6.12< 6.12.85-r0
- linux-aws-6.18< 6.18.31-r0
- linux-azure-6.18< 6.18.31-r0
- linux-gcp-6.12< 6.12.85-r0
- linux-gcp-6.18< 6.18.31-r0
Linux2 products
- linux≥ d646960f7986fefb460a2b062d5ccc8ccfeacc3a, < b2a23529593d011fb433a3d711fc597ed6a6bd2f | ≥ d646960f7986fefb460a2b062d5ccc8ccfeacc3a, < 665315df9c3486cb213fc44d83cc8bcd47fe0d26 | ≥ d646960f7986fefb460a2b062d5ccc8ccfeacc3a, < 9b49e2a4b8219a2fc5cebf94f4ec34e509aff8a6 | ≥ d646960f7986fefb460a2b062d5ccc8ccfeacc3a, < 0eb1263a3b8c36418c9ba295c9ab3abed664edbf | ≥ d646960f7986fefb460a2b062d5ccc8ccfeacc3a, < 796e0cac058252d0ad34ebe288e6f7979b5fc9b2 | ≥ d646960f7986fefb460a2b062d5ccc8ccfeacc3a, < 8977fad2b3c6eefd414131168d597c5d1d5e1abf | ≥ d646960f7986fefb460a2b062d5ccc8ccfeacc3a, < ff3d9e8f7244293e303f7b6ef70774291c7c27e9 | ≥ d646960f7986fefb460a2b062d5ccc8ccfeacc3a, < aba4712e8f0381cd5d196534ce2ad082626a5ab6 | ≥ d646960f7986fefb460a2b062d5ccc8ccfeacc3a, < 2b5dd4632966c39da6ba74dbc8689b309065e82c | 3.3
- linux_kernel≥ 3.3, < 6.6.136 | ≥ 6.7, < 6.12.83 | ≥ 6.13, < 6.18.24 | ≥ 6.19, < 6.19.14 | ≥ 7.0, < 7.0.1
Debian1 product
- linux< 6.1.176-1 | < 6.12.85-1 | < 6.19.14-1
4 vendors · 171 products
