Is CVE-2025-9784 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2025-9784 being exploited in the wild.

How severe is CVE-2025-9784?

High severity, with a CVSS score of 7.5, published 2 September 2025.

Which products and versions are affected?

io.undertow:undertow-core (Maven) ECOSYSTEM:introduced=0,fixed=2.2.38.Final; Red Hat Apache Camel for Spring Boot 4.14.2.

Is there a fix for CVE-2025-9784?

Yes. io.undertow:undertow-core (Maven): upgrade to 2.2.38.Final or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2025-9784 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2025-9784?

Check whether you run io.undertow:undertow-core (Maven) or Red Hat Apache Camel for Spring Boot at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2025-9784: Red Hat Undertow denial of service via MadeYouReset attack

CVE-2025-9784 · Severity: high · CVSS 7.5 · Published 2025-09-02

A vulnerability in the Undertow web server allows remote attackers to overwhelm the system by sending specially crafted HTTP/2 requests. This 'MadeYouReset' attack bypasses standard security counters, potentially leading to a total service outage or significant performance degradation. Organizations using Undertow for web services or application hosting are at risk of denial-of-service attacks.

Technologies: io.undertow:undertow-core (Maven). Vendors: Maven, Red Hat.

Quick answers

Is CVE-2025-9784 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2025-9784 being exploited in the wild.
How severe is CVE-2025-9784?: High severity, with a CVSS score of 7.5, published 2 September 2025.
Which products and versions are affected?: io.undertow:undertow-core (Maven) ECOSYSTEM:introduced=0,fixed=2.2.38.Final; Red Hat Apache Camel for Spring Boot 4.14.2.
Is there a fix for CVE-2025-9784?: Yes. io.undertow:undertow-core (Maven): upgrade to 2.2.38.Final or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2025-9784 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2025-9784?: Check whether you run io.undertow:undertow-core (Maven) or Red Hat Apache Camel for Spring Boot at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

io.undertow:undertow-core (Maven): upgrade to 2.2.38.Final or later

# set io.undertow:undertow-core to 2.2.38.Final in your pom.xml or build.gradle

Technical details

A resource exhaustion vulnerability exists in Undertow's HTTP/2 implementation, specifically regarding how it handles malformed client requests. An attacker can send a sequence of malformed requests that trigger server-side stream resets (RST_STREAM) without incrementing the internal abuse or flood counters. This 'MadeYouReset' attack allows a remote, unauthenticated attacker to induce excessive CPU and memory workload on the server, eventually leading to a denial-of-service (DoS) condition. The issue is rooted in improper resource shutdown and lack of throttling for these specific reset scenarios. Patches are available in versions 2.2.38.Final and 2.3.20.Final.

Affected products

Undertow undertow-core < 2.2.38.Final, >= 2.3.0.Alpha1, < 2.3.20.Final

Identifiers

CVE-2025-9784
GHSA-95h4-w6j8-2rp8

Timeline

2025-09-02: advisory: Initial publication of GHSA-95h4-w6j8-2rp8
2025-09-02: disclosed: NVD publication date
2026-06-30: other: Last updated date

References

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