🛡️ CVE-2021-39162 — envoy

🟠 CVSS 8.0 — High ✅ No Known Exploit OSV
8.0
CVSS Score
0 Low4 Medium7 High9 Critical10

Description

Incorrect handling of H2 GOAWAY + SETTINGS frames

Envoy, which Pomerium is based on, can abnormally terminate if an H/2 GOAWAY and SETTINGS frame are received in the same IO event.

Impact

This can lead to a DoS in the presence of untrusted *upstream* servers.

Patches

0.15.1 contains an upgraded envoy binary with this vulnerability patched.

Workarounds

If only trusted upstreams are configured, there is not substantial risk of this condition being triggered.

References

[envoy GSA](https://github.com/envoyproxy/envoy/security/advisories/GHSA-j374-mjrw-vvp8)

[envoy CVE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-32780)

[envoy announcement](https://groups.google.com/g/envoy-announce/c/5xBpsEZZDfE/m/wD05NZBbAgAJ)

For more information

If you have any questions or comments about this advisory:

Affected software

CVE-2021-39162 is recorded against 2 packages.

  • envoy
  • github.com/pomerium/pomerium

Timeline and source

Published on 6 March 2024 and last revised on 20 May 2025. No public exploit is currently recorded for this entry. Record sourced from OSV.

References

github.com (Web)
github.com (Web)
groups.google.com (Web)
nvd.nist.gov (Web)

Details

Severity HIGH
CVSS Score 8.0
CVSS Vector N/A
CWE N/A
Public Exploit ✅ No
Source OSV
Published 2024-03-06
Updated 2026-08-12
Modified 2025-05-20
Fix URL N/A

Affected Packages

Software From version Fixed in
envoy — —
github.com/pomerium/pomerium — —

Similar Threats

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