{"cve":"CVE-2018-20340","nvd":{"published":"2019-03-21T16:00:35.983","modified":"2026-06-17T01:52:39.347","status":"Modified","description":"Yubico libu2f-host 1.1.6 contains unchecked buffers in devs.c, which could enable a malicious token to exploit a buffer overflow. An attacker could use this to attempt to execute malicious code using a crafted USB device masquerading as a security token on a computer where the affected library is currently in use. It is not possible to perform this attack with a genuine YubiKey.","cvss_v4":null,"cvss_v3":{"version":"3.0","vector":"CVSS:3.0/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","score":6.8},"cwes":["CWE-119"],"references":["https://blog.inhq.net/posts/yubico-libu2f-host-vuln-part1/","https://developers.yubico.com/libu2f-host/Release_Notes.html","https://seclists.org/bugtraq/2019/Feb/23","https://security.gentoo.org/glsa/202004-15","https://www.debian.org/security/2019/dsa-4389"],"products":["debian:debian_linux","yubico:libu2f-host"],"source":"nvd","synced_at":"2026-10-19T20:55:22.313337056+00:00"},"epss":{"cve":"CVE-2018-20340","score":0.00499,"percentile":0.42805,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}