CVE-2021-29258

Name: CVE-2021-29258
Creator: NVD / NIST
Published: 2021-05-20T17:15:07.74+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.5/10EPSS 1.74%

Last modified Jun 17, 2026

CVE-2021-29258 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. 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.. EPSS estimates a 1.74% chance of exploitation in the next 30 days.

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.

Metrics

CVSS 3.1

7.5/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS Probability

1.74%

74.8th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-617

Affected Software

Vendor	Product	Versions
Envoyproxy	Envoy	1.14.6
Envoyproxy	Envoy	1.15.3
Envoyproxy	Envoy	1.16.2
Envoyproxy	Envoy	1.17.1

References

https://blog.envoyproxy.ioVendor Advisory
https://github.com/envoyproxy/envoy-setec/pull/230Broken Link
https://github.com/envoyproxy/envoy/releases/tag/v1.14.0Third Party Advisory
https://github.com/envoyproxy/envoy/security/advisories/GHSA-xw4q-6pj2-5gfgNot Applicable, Third Party Advisory
https://github.com/envoyproxy/envoy/security/advisories/GHSA-rqvq-hxw5-776jThird Party Advisory
https://blog.envoyproxy.ioVendor Advisory
https://github.com/envoyproxy/envoy-setec/pull/230Broken Link
https://github.com/envoyproxy/envoy/releases/tag/v1.14.0Third Party Advisory
https://github.com/envoyproxy/envoy/security/advisories/GHSA-xw4q-6pj2-5gfgNot Applicable, Third Party Advisory

Timeline

Published: May 20, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-29258?

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.

How severe is CVE-2021-29258?

CVE-2021-29258 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 1.74% probability of exploitation in the next 30 days.

How do I fix CVE-2021-29258?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-29258?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST