Entreprise française de cybersécurité depuis 2004
☎ 03 60 47 09 81 - info@securiteinfo.com
☎ 03 60 47 09 81 - info@securiteinfo.com
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.
No PoCs from references.
- https://github.com/Ampferl/poc_http2-continuation-flood
- https://github.com/DrewskyDev/H2Flood
- https://github.com/Vos68/HTTP2-Continuation-Flood-PoC
- https://github.com/blackmagic2023/Envoy-CPU-Exhaustion-Vulnerability-PoC
- https://github.com/lockness-Ko/CVE-2024-27316
- https://github.com/nomi-sec/PoC-in-GitHub