CVE-2025-9784
published 2025-09-02CVE-2025-9784: A flaw was found in Undertow where malformed client requests can trigger server-side stream resets without triggering abuse counters. This issue, referred to…
PriorityP345high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
EPSS
2.33%
83.4th percentile
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
9 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | undertow | < undertow 2.3.20-1 (forky) | undertow 2.3.20-1 (forky) |
| redhat | enterprise_linux | — | — |
| redhat | enterprise_linux | — | — |
| redhat | fuse | — | — |
| redhat | jboss_enterprise_application_platform | — | — |
| redhat | jboss_enterprise_application_platform | — | — |
| redhat | process_automation | — | — |
| redhat | single_sign-on | — | — |
| redhat | undertow | >= 0 < 2.3.20-1 | 2.3.20-1 |
CVSS provenance
nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
osv7.5HIGH
vendor_debian7.5HIGH
vendor_redhat7.5HIGH
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OSV
Undertow MadeYouReset HTTP/2 DDoS Vulnerability
osv·2025-09-02
CVE-2025-9784 [HIGH] Undertow MadeYouReset HTTP/2 DDoS Vulnerability
Undertow MadeYouReset HTTP/2 DDoS Vulnerability
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).
OSV
CVE-2025-9784: A flaw was found in Undertow where malformed client requests can trigger server-side stream resets without triggering abuse counters
osv·2025-09-02·CVSS 7.5
CVE-2025-9784 [HIGH] CVE-2025-9784: A flaw was found in Undertow where malformed client requests can trigger server-side stream resets without triggering abuse counters
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).
GHSA
Undertow MadeYouReset HTTP/2 DDoS Vulnerability
ghsa·2025-09-02
CVE-2025-9784 [HIGH] CWE-404 Undertow MadeYouReset HTTP/2 DDoS Vulnerability
Undertow MadeYouReset HTTP/2 DDoS Vulnerability
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).
Red Hat
kernel: hfsplus: fix slab-out-of-bounds in hfsplus_bnode_read()
vendor_redhat·2025-09-04·CVSS 7.1
CVE-2025-38714 [HIGH] CWE-125 kernel: hfsplus: fix slab-out-of-bounds in hfsplus_bnode_read()
kernel: hfsplus: fix slab-out-of-bounds in hfsplus_bnode_read()
In the Linux kernel, the following vulnerability has been resolved:
hfsplus: fix slab-out-of-bounds in hfsplus_bnode_read()
The hfsplus_bnode_read() method can trigger the issue:
[ 174.852007][ T9784] ==================================================================
[ 174.852709][ T9784] BUG: KASAN: slab-out-of-bounds in hfsplus_bnode_read+0x2f4/0x360
[ 174.853412][ T9784] Read of size 8 at addr ffff88810b5fc6c0 by task repro/9784
[ 174.854059][ T9784]
[ 174.854272][ T9784] CPU: 1 UID: 0 PID: 9784 Comm: repro Not tainted 6.16.0-rc3 #7 PREEMPT(full)
[ 174.854281][ T9784] Hardware name: QEMU Ubuntu 24.04 PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
[ 174.854286][ T9784] Call Trace:
[ 174.854289][ T9784]
[ 1
Red Hat
undertow: Undertow MadeYouReset HTTP/2 DDoS Vulnerability
vendor_redhat·2025-09-01·CVSS 7.5
CVE-2025-9784 [HIGH] CWE-770 undertow: Undertow MadeYouReset HTTP/2 DDoS Vulnerability
undertow: Undertow MadeYouReset HTTP/2 DDoS Vulnerability
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).
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
Debian
CVE-2025-9784: undertow - A flaw was found in Undertow where malformed client requests can trigger server-...
vendor_debian·2025·CVSS 7.5
CVE-2025-9784 [HIGH] CVE-2025-9784: undertow - A flaw was found in Undertow where malformed client requests can trigger server-...
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).
Scope: local
forky: resolved (fixed in 2.3.20-1)
sid: resolved (fixed in 2.3.20-1)
No detection rules found.
No public exploits indexed.
Bugzilla
CVE-2025-9784 undertow: Undertow MadeYouReset HTTP/2 DDoS Vulnerability
bugzilla·2025-09-01·CVSS 7.5
CVE-2025-9784 [HIGH] CVE-2025-9784 undertow: Undertow MadeYouReset HTTP/2 DDoS Vulnerability
CVE-2025-9784 undertow: Undertow MadeYouReset HTTP/2 DDoS Vulnerability
HTTP/2 (including DNS over HTTPS) contains a design flaw and is vulnerable to "MadeYouReset" DoS attack through HTTP/2 control frames
Discussion:
This issue has been addressed in the following products:
Red Hat build of Apache Camel 4.14.2 for Spring Boot 3.5.8
Via RHSA-2025:23143 https://access.redhat.com/errata/RHSA-2025:23143
---
This issue has been addressed in the following products:
Red Hat JBoss Enterprise Application Platform 8.1
Via RHSA-2026:0386 https://access.redhat.com/errata/RHSA-2026:0386
---
This issue has been addressed in the following products:
Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 8
Via RHSA-2026:0383 https://access.redhat.com/errata/RHSA-2026:0383
---
This issue
Bugzilla
[Minor Incident] CVE-2025-9784 resteasy: Undertow MadeYouReset HTTP/2 DDoS Vulnerability [fedora-all]
bugzilla·2025-09-01·CVSS 7.5
CVE-2025-9784 [HIGH] [Minor Incident] CVE-2025-9784 resteasy: Undertow MadeYouReset HTTP/2 DDoS Vulnerability [fedora-all]
[Minor Incident] CVE-2025-9784 resteasy: Undertow MadeYouReset HTTP/2 DDoS Vulnerability [fedora-all]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
The following link provides references to all essential vulnerability management information. If something is wrong or missing, please contact a member of PSIRT.
https://spaces.redhat.com/display/PRODSEC/Vulnerability+Management+-+Essential+Documents+for+Engineering+Teams
Discussion:
This message is a reminder that Fedora Linux 42 is nearing its end of life.
Fedora will stop maintaining and issuing updates for Fedora Linux 42 on 2026-05-13.
It is Fedora's policy to
https://access.redhat.com/errata/RHSA-2025:23143https://access.redhat.com/errata/RHSA-2026:0383https://access.redhat.com/errata/RHSA-2026:0384https://access.redhat.com/errata/RHSA-2026:0386https://access.redhat.com/errata/RHSA-2026:33371https://access.redhat.com/errata/RHSA-2026:33372https://access.redhat.com/errata/RHSA-2026:3889https://access.redhat.com/errata/RHSA-2026:3891https://access.redhat.com/errata/RHSA-2026:3892https://access.redhat.com/errata/RHSA-2026:4915https://access.redhat.com/errata/RHSA-2026:4916https://access.redhat.com/errata/RHSA-2026:4917https://access.redhat.com/errata/RHSA-2026:4924https://access.redhat.com/errata/RHSA-2026:76128https://access.redhat.com/errata/RHSA-2026:76129https://access.redhat.com/errata/RHSA-2026:76130https://access.redhat.com/errata/RHSA-2026:76132https://access.redhat.com/errata/RHSA-2026:76134https://access.redhat.com/security/cve/CVE-2025-9784https://bugzilla.redhat.com/show_bug.cgi?id=2392306https://github.com/undertow-io/undertow/pull/1778https://github.com/undertow-io/undertow/releases/tag/2.2.38.Finalhttps://issues.redhat.com/browse/UNDERTOW-2598https://kb.cert.org/vuls/id/767506https://www.kb.cert.org/vuls/id/767506
2025-09-02
Published