{"id":"BIT-envoy-2024-30255","summary":"HTTP/2: CPU exhaustion due to CONTINUATION frame flood","details":"Envoy is a cloud-native, open source edge and service proxy. The HTTP/2 protocol stack in Envoy versions prior to 1.29.3, 1.28.2, 1.27.4, and 1.26.8 are vulnerable to CPU exhaustion due to flood of CONTINUATION frames. Envoy's HTTP/2 codec allows the client to send an unlimited number of CONTINUATION frames even after exceeding Envoy's header map limits. This allows an attacker to send a sequence of CONTINUATION frames without the END_HEADERS bit set causing CPU utilization, consuming approximately 1 core per 300Mbit/s of traffic and culminating in denial of service through CPU exhaustion. Users should upgrade to version 1.29.3, 1.28.2, 1.27.4, or 1.26.8 to mitigate the effects of the CONTINUATION flood. As a workaround, disable HTTP/2 protocol for downstream connections.","aliases":["CVE-2024-30255","GHSA-j654-3ccm-vfmm"],"modified":"2026-09-08T08:47:27.664808618Z","published":"2024-04-06T18:17:53.965Z","database_specific":{"severity":"High","cpes":["cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*"]},"references":[{"type":"ADVISORY","url":"https://github.com/envoyproxy/envoy/security/advisories/GHSA-j654-3ccm-vfmm"},{"type":"ADVISORY","url":"http://www.openwall.com/lists/oss-security/2024/04/03/16"},{"type":"DISCUSSION","url":"http://www.openwall.com/lists/oss-security/2024/04/05/3"},{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2024-30255"},{"type":"WEB","url":"https://www.kb.cert.org/vuls/id/421644"}],"affected":[{"package":{"name":"envoy","ecosystem":"Bitnami","purl":"pkg:bitnami/envoy"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"1.26.8"},{"introduced":"1.27.0"},{"fixed":"1.27.4"},{"introduced":"1.28.0"},{"fixed":"1.28.2"},{"introduced":"1.29.0"},{"fixed":"1.29.3"}]}],"database_specific":{"source":"https://github.com/bitnami/vulndb/tree/main/data/envoy/BIT-envoy-2024-30255.json"},"severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"}]}],"schema_version":"1.9.0"}