CVE-2018-20340

MediumCVSS 6.8/10Last modified Jun 17, 2026

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.

Metrics

CVSS 3.0 6.8/10CVSS:3.0/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Weakness enumeration

CWE-119

Affected software

Vendor	Product	Versions
n/a	n/a	n/a

References

https://blog.inhq.net/posts/yubico-libu2f-host-vuln-part1/
https://developers.yubico.com/libu2f-host/Release_Notes.htmlRelease Notes, Vendor Advisory
https://seclists.org/bugtraq/2019/Feb/23Mailing List, Third Party Advisory
https://security.gentoo.org/glsa/202004-15
https://www.debian.org/security/2019/dsa-4389Third Party Advisory
https://www.yubico.com/support/security-advisories/ysa-2019-01/Patch, Vendor Advisory
https://blog.inhq.net/posts/yubico-libu2f-host-vuln-part1/
https://developers.yubico.com/libu2f-host/Release_Notes.htmlRelease Notes, Vendor Advisory
https://seclists.org/bugtraq/2019/Feb/23Mailing List, Third Party Advisory
https://security.gentoo.org/glsa/202004-15
https://www.debian.org/security/2019/dsa-4389Third Party Advisory
https://www.yubico.com/support/security-advisories/ysa-2019-01/Patch, Vendor Advisory

Timeline

Published: Mar 21, 2019
Last modified: Jun 17, 2026
NVD status: Modified

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