# CVE-2025-9784

## Summary

- **CVE ID:** CVE-2025-9784
- **Severity:** HIGH
- **CVSS Score:** 7.5 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)
- **CWE:** CWE-770
- **Published:** Sep 2, 2025
- **Last Modified:** Sep 4, 2026

## Description

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 Products

- Unknown product (0)
- Red Hat — Red Hat JBoss Enterprise Application Platform 8.0 for RHEL 8 (0:1.83.0-1.redhat_00001.1.el8eap)
- Red Hat — Red Hat JBoss Enterprise Application Platform 8.0 for RHEL 8 (0:33.0.0-2.jre_redhat_00003.1.el8eap)
- Red Hat — Red Hat JBoss Enterprise Application Platform 8.0 for RHEL 8 (0:4.0.6-1.redhat_00001.1.el8eap)
- Red Hat — Red Hat JBoss Enterprise Application Platform 8.0 for RHEL 8 (0:1.0.0-3.redhat_00009.1.el8eap)
- Red Hat — Red Hat JBoss Enterprise Application Platform 8.0 for RHEL 8 (0:2.0.2-1.Final_redhat_00001.1.el8eap)
- Red Hat — Red Hat JBoss Enterprise Application Platform 8.0 for RHEL 8 (0:2.3.23-1.SP3_redhat_00001.1.el8eap)
- Red Hat — Red Hat JBoss Enterprise Application Platform 8.0 for RHEL 9 (0:1.83.0-1.redhat_00001.1.el9eap)
- Red Hat — Red Hat JBoss Enterprise Application Platform 8.0 for RHEL 9 (0:33.0.0-2.jre_redhat_00003.1.el9eap)
- Red Hat — Red Hat JBoss Enterprise Application Platform 8.0 for RHEL 9 (0:4.0.6-1.redhat_00001.1.el9eap)
- Red Hat — Red Hat JBoss Enterprise Application Platform 8.0 for RHEL 9 (0:1.0.0-3.redhat_00009.1.el9eap)
- Red Hat — Red Hat JBoss Enterprise Application Platform 8.0 for RHEL 9 (0:2.0.2-1.Final_redhat_00001.1.el9eap)
- Red Hat — Red Hat JBoss Enterprise Application Platform 8.0 for RHEL 9 (0:2.3.23-1.SP3_redhat_00001.1.el9eap)
- Red Hat — Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 8 (0:2.3.20-2.SP4_redhat_00001.1.el8eap)
- Red Hat — Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 9 (0:2.3.20-2.SP4_redhat_00001.1.el9eap)
- Red Hat — Red Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 7 (0:2.2.39-1.Final_redhat_00001.1.el7eap)
- Red Hat — Red Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 7 (0:7.4.24-4.GA_redhat_00002.1.el7eap)
- Red Hat — Red Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 8 (0:2.2.39-1.Final_redhat_00001.1.el8eap)
- Red Hat — Red Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 8 (0:7.4.24-4.GA_redhat_00002.1.el8eap)
- Red Hat — Red Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 9 (0:2.2.39-1.Final_redhat_00001.1.el9eap)
- Red Hat — Red Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 9 (0:7.4.24-4.GA_redhat_00002.1.el9eap)
- Red Hat — Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 8 (0:4.0.10-1.redhat_00001.1.el8eap)
- Red Hat — Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 8 (0:1.82.0-1.redhat_00001.1.el8eap)
- Red Hat — Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 8 (0:801.3.0-1.GA_redhat_00001.1.el8eap)
- Red Hat — Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 8 (0:1.0.1-3.redhat_00003.1.el8eap)
- Red Hat — Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 8 (0:6.6.36-1.Final_redhat_00001.1.el8eap)
- Red Hat — Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 8 (0:4.0.2-1.Final_redhat_00001.1.el8eap)
- Red Hat — Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 8 (0:2.5.0-1.redhat_00001.1.el8eap)
- Red Hat — Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 8 (0:8.1.3-4.GA_redhat_00006.1.el8eap)
- Red Hat — Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 8 (0:5.0.12-1.Final_redhat_00001.1.el8eap)
- Red Hat — Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 8 (0:2.6.6-1.Final_redhat_00001.1.el8eap)
- Red Hat — Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 8 (0:8.1.1-4.GA_redhat_00007.1.el8eap)
- Red Hat — Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 9 (0:4.0.10-1.redhat_00001.1.el9eap)
- Red Hat — Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 9 (0:1.82.0-1.redhat_00001.1.el9eap)
- Red Hat — Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 9 (0:801.3.0-1.GA_redhat_00001.1.el9eap)
- Red Hat — Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 9 (0:1.0.1-3.redhat_00003.1.el9eap)
- Red Hat — Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 9 (0:6.6.36-1.Final_redhat_00001.1.el9eap)
- Red Hat — Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 9 (0:4.0.2-1.Final_redhat_00001.1.el9eap)
- Red Hat — Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 9 (0:2.5.0-1.redhat_00001.1.el9eap)
- Red Hat — Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 9 (0:8.1.3-4.GA_redhat_00006.1.el9eap)
- Red Hat — Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 9 (0:5.0.12-1.Final_redhat_00001.1.el9eap)
- Red Hat — Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 9 (0:2.6.6-1.Final_redhat_00001.1.el9eap)
- Red Hat — Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 9 (0:8.1.1-4.GA_redhat_00007.1.el9eap)
- Red Hat — Red Hat JBoss Enterprise Application Platform (2.2.39.Final-redhat-00001)
- Red Hat — Red Hat JBoss Enterprise Application Platform 7.1 EUS for RHEL 7 (0:1.4.18-21.SP19_redhat_00001.1.ep7.el7)
- Red Hat — Red Hat JBoss Enterprise Application Platform 7.3 EUS for RHEL 7 (0:2.0.41-8.SP9_redhat_00001.1.el7eap)
- Red Hat — Red Hat JBoss Enterprise Application Platform 7.4.24 (2.2.39.Final-redhat-00001)
- Red Hat — Red Hat JBoss Enterprise Application Platform 8.1.6 (2.3.24.SP2-redhat-00001)

## References

- [CNA](https://access.redhat.com/errata/RHSA-2025:23143)
- [CNA](https://access.redhat.com/errata/RHSA-2026:0383)
- [CNA](https://access.redhat.com/errata/RHSA-2026:0384)
- [CNA](https://access.redhat.com/errata/RHSA-2026:0386)
- [CNA](https://access.redhat.com/errata/RHSA-2026:3889)
- [CNA](https://access.redhat.com/errata/RHSA-2026:3891)
- [CNA](https://access.redhat.com/errata/RHSA-2026:3892)
- [CNA](https://access.redhat.com/security/cve/CVE-2025-9784)
- [CNA](https://bugzilla.redhat.com/show_bug.cgi?id=2392306)
- [CNA](https://github.com/undertow-io/undertow/pull/1778)
- [CNA](https://github.com/undertow-io/undertow/releases/tag/2.2.38.Final)
- [CNA](https://issues.redhat.com/browse/UNDERTOW-2598)
- [CNA](https://kb.cert.org/vuls/id/767506)
- [CVE](https://www.kb.cert.org/vuls/id/767506)
- [CNA](https://access.redhat.com/errata/RHSA-2026:4915)
- [CNA](https://access.redhat.com/errata/RHSA-2026:4916)
- [CNA](https://access.redhat.com/errata/RHSA-2026:4917)
- [CNA](https://access.redhat.com/errata/RHSA-2026:4924)
- [CNA](https://access.redhat.com/errata/RHSA-2026:33371)
- [CNA](https://access.redhat.com/errata/RHSA-2026:33372)

## Exploitation Prediction (EPSS)

- **EPSS Score:** 2.33%
- **EPSS Percentile:** 82.6

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_Exported from OnDuty AI Vulnerability Intelligence on 2026-09-17._