CVE-2020-8660

Severity: medium (CVSS 5.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2020-03-04 · updated 2026-06-17
Weakness: CWE-345

Description

CNCF Envoy through 1.13.0 TLS inspector bypass. TLS inspector could have been bypassed (not recognized as a TLS client) by a client using only TLS 1.3. Because TLS extensions (SNI, ALPN) were not inspected, those connections might have been matched to a wrong filter chain, possibly bypassing some security restrictions in the process.

Affected products

envoyproxy envoy: before 1.12.3; from 1.13.0 before 1.13.1 — fixed in 1.12.3, 1.13.1

How to fix

Upgrade to a fixed version: envoyproxy envoy 1.12.3, 1.13.1. Check the vendor advisory for mitigations.

References

https://access.redhat.com/errata/RHSA-2020:0734
https://github.com/envoyproxy/envoy/security/advisories/GHSA-c4g8-7grc-5wvx
https://www.envoyproxy.io/docs/envoy/v1.13.1/intro/version_history
https://access.redhat.com/errata/RHSA-2020:0734
https://github.com/envoyproxy/envoy/security/advisories/GHSA-c4g8-7grc-5wvx
https://www.envoyproxy.io/docs/envoy/v1.13.1/intro/version_history

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