CVE-2021-28683

HIGH 7.5CVE-2021-28683 · Published 20/05/2021 · updated 17/06/2026

In short

CVE-2021-28683 is a HIGH (CVSS 7.5) vulnerability affecting envoy (envoyproxy).
Chance of exploitation in the next 30 days (EPSS): 1.7%, higher than 77.0% of all vulnerabilities.
No patched version is listed yet: follow the vendor's advisory in References.

Package	Affected versions	Patched versions
envoy envoyproxy	`= 1.16.2= 1.17.1`	No fix yet

Description

An issue was discovered in Envoy through 1.71.1. There is a remotely exploitable NULL pointer dereference and crash in TLS when an unknown TLS alert code is received.

References

blog.envoyproxy.io · Vendor Advisory
envoyproxy/envoy release · Third Party Advisory
envoyproxy/envoy security advisory · Not Applicable
envoyproxy/envoy security advisory · Third Party Advisory

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Package

Affected versions

Patched versions

envoy

envoyproxy

= 1.16.2= 1.17.1

No fix yet

More vulnerabilities in envoy

See all →