Description
The sync endpoint in YubiKey Validation Server before 2.40 allows remote attackers to replay an OTP. NOTE: this issue is potentially relevant to persons outside Yubico who operate a self-hosted OTP validation service with a non-default configuration such as an open sync pool; the issue does NOT affect YubiCloud.
References (3)
Core 3
Core References
Exploit, Vendor Advisory x_refsource_misc
https://www.yubico.com/support/security-advisories/ysa-2020-01/
Release Notes, Third Party Advisory x_refsource_misc
https://github.com/Yubico/yubikey-val/releases/tag/yubikey-val-2.40
Mailing List mailing-list
x_refsource_mlist
https://lists.debian.org/debian-lts-announce/2020/03/msg00014.html
Scores
CVSS v3
8.6
EPSS
0.0145
EPSS Percentile
69.8%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H
Details
CWE
CWE-294
Status
published
Products (1)
yubico/yubikey_one_time_password_validation_server
< 2.40
Published
Mar 05, 2020
Tracked Since
Feb 18, 2026