How severe is CVE-2019-20894?

CVE-2019-20894 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2019-20894 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (72nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-20894?

CVE-2019-20894 affects Traefik. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2019-20894?

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-2019-20894 published?

CVE-2019-20894 was published on 2020-07-02 and last updated on 2026-06-17.

CVE-2019-20894

CVE-2019-20894 is a high-severity vulnerability in Traefik with a CVSS 3.x base score of 7.5. 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-295.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 4.3
EPSS exploit prediction: 2% (72nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-295
Affected product: Traefik
Published: 2020-07-02
Last modified: 2026-06-17

Description

Traefik 2.x, in certain configurations, allows HTTPS sessions to proceed without mutual TLS verification in a situation where ERR_BAD_SSL_CLIENT_AUTH_CERT should have occurred.

Frequently asked questions

What is CVE-2019-20894?: Traefik 2.x, in certain configurations, allows HTTPS sessions to proceed without mutual TLS verification in a situation where ERR_BAD_SSL_CLIENT_AUTH_CERT should have occurred.
How severe is CVE-2019-20894?: CVE-2019-20894 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2019-20894 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (72nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-20894?: CVE-2019-20894 affects Traefik. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2019-20894?: 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-2019-20894 published?: CVE-2019-20894 was published on 2020-07-02 and last updated on 2026-06-17.

References

https://github.com/containous/traefik/issues/5312

Affected products (1)

cpe:2.3:a:traefik:traefik:*:*:*:*:*:*:*:*

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