CVE-2021-32778
Vulnerability from cvelistv5
Published
2021-08-24 20:30
Modified
2024-08-03 23:33
Severity ?
5.8 (Medium) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L
EPSS score ?
0.07% (0.18813)
Summary
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
security-advisories@github.comhttps://github.com/envoyproxy/envoy/security/advisories/GHSA-3xh3-33v5-chccThird Party Advisory
security-advisories@github.comhttps://www.envoyproxy.io/docs/envoy/v1.19.0/version_history/version_historyRelease Notes, Vendor Advisory
af854a3a-2127-422b-91ae-364da2661108https://github.com/envoyproxy/envoy/security/advisories/GHSA-3xh3-33v5-chccThird Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://www.envoyproxy.io/docs/envoy/v1.19.0/version_history/version_historyRelease Notes, Vendor Advisory
Impacted products
Vendor Product Version
envoyproxy envoy Version: >= 1.19.0, < 1.19.1
Version: >= 1.18.0, < 1.18.4
Version: >= 1.17.0, < 1.17.4
Version: >= 1.16.0, < 1.16.5
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