CVE-2021-32778
- Source
- https://cve.org/CVERecord?id=CVE-2021-32778
- Import Source
- https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-32778.json
- JSON Data
- https://api.osv.dev/v1/vulns/CVE-2021-32778
- Aliases
- Downstream
- Published
- 2021-08-24T21:15:09.553Z
- Modified
- 2026-07-09T10:01:32.173727Z
- Severity
-
- 7.5 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H CVSS Calculator
- Summary
- [none]
- Details
-
Envoy is an open source L7 proxy and communication bus designed for large modern service oriented architectures. In affected versions envoy’s procedure for resetting a HTTP/2 stream has O(N^2) complexity, leading to high CPU utilization when a large number of streams are reset. Deployments are susceptible to Denial of Service when Envoy is configured with high limit on H/2 concurrent streams. An attacker wishing to exploit this vulnerability would require a client opening and closing a large number of H/2 streams. Envoy versions 1.19.1, 1.18.4, 1.17.4, 1.16.5 contain fixes to reduce time complexity of resetting HTTP/2 streams. As a workaround users may limit the number of simultaneous HTTP/2 dreams for upstream and downstream peers to a low number, i.e. 100.
- References
Affected packages
Git / github.com/envoyproxy/envoy
Affected ranges
- Type
- GIT
- Repo
- https://github.com/envoyproxy/envoy
- Events
-
IntroducedFixedIntroducedFixedIntroducedFixedIntroducedLast affected
- Database specific
{ "source": [ "CPE_RANGE", "CPE_STRING" ], "cpe": [ "cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*", "cpe:2.3:a:envoyproxy:envoy:1.19.0:*:*:*:*:*:*:*" ], "extracted_events": [ { "introduced": "1.16.0" }, { "fixed": "1.16.5" }, { "introduced": "1.17.0" }, { "fixed": "1.17.4" }, { "introduced": "1.18.0" }, { "fixed": "1.18.4" }, { "introduced": "1.19.0" }, { "last_affected": "1.19.0" } ] }