What is CVE-2021-21378?

CVE-2021-21378 is a high-severity vulnerability in Envoyproxy Envoy, classified under Improper Authentication. CVSS score: 8.2/10. Published 2021-03-11.

How severe is CVE-2021-21378?

High severity. CVSS v3 base score is 8.2 out of 10.

Is CVE-2021-21378 known to be exploited?

1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Auth bypass in Envoyproxy Envoy

CVE-2021-21378

Envoy is a cloud-native high-performance edge/middle/service proxy. In Envoy version 1.17.0 an attacker can bypass authentication by presenting a JWT token with an issuer that is not in the provider list when Envoy's JWT Authentication fil…

Vulnerability class: Broken Authentication

EPSS: 0.004 (62.4th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.2 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N.

Affected products

Envoyproxy Envoy — versions = 1.17.0

Weakness classification (CWE)

Public proof-of-concept exploits

Live-Hack-CVE/CVE-2021-21378

References

github.com/envoyproxy/envoy/security/advisories/GHSA-4996-m8hf-hj27 (x_refsource_CONFIRM)
github.com/envoyproxy/envoy/pull/15194 (x_refsource_MISC)
github.com/envoyproxy/envoy/commit/ea39e3cba652bcc4b11bb0d5c62b017e584d2e5a (x_refsource_MISC)

Frequently asked questions

What is CVE-2021-21378?: CVE-2021-21378 is a high-severity vulnerability in Envoyproxy Envoy, classified under Improper Authentication. CVSS score: 8.2/10. Published 2021-03-11.
How severe is CVE-2021-21378?: High severity. CVSS v3 base score is 8.2 out of 10.
Is CVE-2021-21378 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.