CVE-2021-29258

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.8% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-05-20 · updated 2026-06-17
Weakness: CWE-617

Description

An issue was discovered in Envoy 1.14.0. There is a remotely exploitable crash for HTTP2 Metadata, because an empty METADATA map triggers a Reachable Assertion.

Affected products

envoyproxy envoy: 1.14.6, 1.15.3, 1.16.2, 1.17.1

References

https://blog.envoyproxy.io
https://github.com/envoyproxy/envoy-setec/pull/230
https://github.com/envoyproxy/envoy/releases/tag/v1.14.0
https://github.com/envoyproxy/envoy/security/advisories/GHSA-xw4q-6pj2-5gfg
https://github.com/envoyproxy/envoy/security/advisories/GHSA-rqvq-hxw5-776j
https://blog.envoyproxy.io
https://github.com/envoyproxy/envoy-setec/pull/230
https://github.com/envoyproxy/envoy/releases/tag/v1.14.0
https://github.com/envoyproxy/envoy/security/advisories/GHSA-xw4q-6pj2-5gfg

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