How severe is CVE-2020-10185?

CVE-2020-10185 has a CVSS 3.x base score of 8.6, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability high.

Is CVE-2020-10185 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (70th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-10185?

CVE-2020-10185 affects Yubico Yubikey One Time Password Validation Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-10185?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2020-10185 published?

CVE-2020-10185 was published on 2020-03-05 and last updated on 2026-06-17.

CVE-2020-10185

CVE-2020-10185 is a high-severity vulnerability in Yubico Yubikey One Time Password Validation Server with a CVSS 3.x base score of 8.6. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-294.

Key facts

Severity: High (CVSS 3.x base score 8.6)
CVSS v2: 6.8
EPSS exploit prediction: 1% (70th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-294
Affected product: Yubico Yubikey One Time Password Validation Server
Published: 2020-03-05
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2020-10185?: 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.
How severe is CVE-2020-10185?: CVE-2020-10185 has a CVSS 3.x base score of 8.6, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability high.
Is CVE-2020-10185 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (70th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-10185?: CVE-2020-10185 affects Yubico Yubikey One Time Password Validation Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-10185?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2020-10185 published?: CVE-2020-10185 was published on 2020-03-05 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:yubico:yubikey_one_time_password_validation_server:*:*:*:*:*:*:*:*

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