high7.5
CVE-2025-9784
Undertow MadeYouReset HTTP/2 DDoS Vulnerability
Impact
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).
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| maven | io.undertow:undertow-core | < 2.2.38.Final | 2.2.38.Final |
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Redhat | Build Of Apache Camel For Spring Boot | All versions |
| Redhat | Fuse | Version 7.0.0 |
| Redhat | Jboss Enterprise Application Platform | Versions 7.0.0, 8.0.0 |
| Redhat | Jboss Enterprise Application Platform Expansion Pack | All versions |
| Redhat | Process Automation | Version 7.0 |
| Redhat | Single Sign-On | Version 7.0 |
| Redhat | Undertow | All versions |
| Redhat | Enterprise Linux | Versions 8.0, 9.0 |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://access.redhat.com/errata/RHSA-2025:23143
- https://access.redhat.com/errata/RHSA-2026:0383
- https://access.redhat.com/errata/RHSA-2026:0384
- https://access.redhat.com/errata/RHSA-2026:0386
- https://access.redhat.com/errata/RHSA-2026:33371
- https://access.redhat.com/errata/RHSA-2026:33372
- https://access.redhat.com/errata/RHSA-2026:3889
- https://access.redhat.com/errata/RHSA-2026:3891
- https://access.redhat.com/errata/RHSA-2026:3892
- https://access.redhat.com/errata/RHSA-2026:4915
- https://access.redhat.com/errata/RHSA-2026:4916
- https://access.redhat.com/errata/RHSA-2026:4917
- https://access.redhat.com/errata/RHSA-2026:4924
- https://access.redhat.com/errata/RHSA-2026:76128
- https://access.redhat.com/errata/RHSA-2026:76129
- https://access.redhat.com/errata/RHSA-2026:76130
- https://access.redhat.com/errata/RHSA-2026:76132
- https://access.redhat.com/errata/RHSA-2026:76134
- https://access.redhat.com/security/cve/CVE-2025-9784
- https://bugzilla.redhat.com/show_bug.cgi?id=2392306
- https://github.com/undertow-io/undertow/pull/1778
- https://github.com/undertow-io/undertow/releases/tag/2.2.38.Final
- https://issues.redhat.com/browse/UNDERTOW-2598
- https://kb.cert.org/vuls/id/767506
- https://www.kb.cert.org/vuls/id/767506