High severity · published Sep 2, 2025
CVE-2025-9784
Undertow: undertow madeyoureset http/2 ddos vulnerability
7.5
CVSS
2.3%
EPSS
No
On KEV
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).
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)2.3% · higher than 83% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
RB
RHEL-8 based Middleware Containers · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat Data Grid 8 · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat Fuse 7 · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat JBoss Enterprise Application Platform 7 · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat JBoss Enterprise Application Platform 7.1 EUS for RHEL 7 · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat JBoss Enterprise Application Platform 7.3 EUS for RHEL 7 · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 7 · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 8 · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 9 · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat JBoss Enterprise Application Platform 7.4.24 · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat JBoss Enterprise Application Platform 8.0 for RHEL 8 · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat JBoss Enterprise Application Platform 8.0 for RHEL 9 · Red Hat
All versions, or not specified · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-9784
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-9784
vendor-advisory
https://access.redhat.com/errata/RHSA-2025:23143
vendor-advisory
https://access.redhat.com/errata/RHSA-2026:0383
vendor-advisory
https://access.redhat.com/errata/RHSA-2026:0384
vendor-advisory
https://access.redhat.com/errata/RHSA-2026:0386
vendor-advisory
https://access.redhat.com/errata/RHSA-2026:33371
vendor-advisory
https://access.redhat.com/errata/RHSA-2026:33372
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