CVE-2026-44909

Proxygen lacked a generalized slow-consumer detection mechanism in its core HTTP session layer. A remote, unauthenticated attacker could exploit HTTP/2 flow-control by setting SETTINGSINITIALWINDOWSIZE to 0 or withholding WINDOWUPDATE frames, causing the server to buffer complete response bodies ...

Denial-of-service vulnerability in HTTP/2 servers via stalled flow-control conditions

Overview A denial-of-service DoS vulnerability exists in some HTTP/2 server implementations that fail to adequately limit resource consumption when buffering response data under stalled flow-control conditions. A remote, unauthenticated attacker can trigger memory exhaustion and service...

Apache HTTP Server: DoS in HTTP/2 with initial windows size 0

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