CVE-2021-32778
Fixed in a distro release EPSS 1%CVSS 5.8
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.
Products: envoyproxy envoy
Distro releases
| Release | Package | Fixed in |
|---|---|---|
| Arch Linux | istio | 1.11.1-1 |
| Red Hat service mesh 2.1 | servicemesh | 0:2.1.0-5.el8 |
| Red Hat service mesh 2.1 | servicemesh-cni | 0:2.1.0-5.el8 |
| Red Hat service mesh 2.1 | servicemesh-grafana | 0:7.2.1-2.el8 |
| Red Hat service mesh 2.1 | servicemesh-grafana-debuginfo | 0:7.2.1-2.el8 |
| Red Hat service mesh 2.1 | servicemesh-operator | 0:2.1.0-4.el8 |
| Red Hat service mesh 2.1 | servicemesh-pilot-agent | 0:2.1.0-5.el8 |
| Red Hat service mesh 2.1 | servicemesh-pilot-discovery | 0:2.1.0-5.el8 |
| Red Hat service mesh 2.1 | servicemesh-prometheus | 0:2.23.0-1.el8 |
| Red Hat service mesh 2.1 | servicemesh-proxy | 0:2.1.0-13.el8 |
| Red Hat service mesh 2.1 | servicemesh-proxy-debuginfo | 0:2.1.0-13.el8 |
| Red Hat service mesh 2.1 | servicemesh-proxy-debugsource | 0:2.1.0-13.el8 |
| Red Hat service mesh 2.1 | servicemesh-proxy-wasm | 0:2.1.0-13.el8 |
| Red Hat service mesh 2.1 | servicemesh-ratelimit | 0:2.1.0-1.el8 |