CVE-2025-9784: Undertow MadeYouReset HTTP/2 DDoS Vulnerability

(updated )

A flaw was found in Undertow where malformed client requests can trigger server-side stream resets without triggering abuse counters. This issue, referred to as the “MadeYouReset” attack, allows malicious clients to induce excessive server workload by repeatedly causing server-side stream aborts. While not a protocol bug, this highlights a common implementation weakness that can be exploited to cause a denial of service (DoS).

References

Code Behaviors & Features

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