High severity · published Aug 11, 2026
CVE-2026-15561
Undertow-core: oom via missing limits in chunked trailer in eap's undertow
7.5
CVSS
0.8%
EPSS
No
On KEV
Description
A flaw was found in EAP's undertow http/1.1 chunked-transfer decoder. missing limits on size and count would allow an attacker to use an unauthenticated connection to drive the JVM to an OutOfMemory error, stopping all deployments on the listener, and achieving Denial of Service.
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)0.8% · higher than 58% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
RH
Red Hat JBoss Enterprise Application Platform 7 · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat JBoss Enterprise Application Platform 7.4 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 8.1 for RHEL 10 · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 8 · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 9 · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat JBoss Enterprise Application Platform 8.1.8.GA · Red Hat
All versions, or not specified · source: vendor
Affected product
RH
Red Hat JBoss Enterprise Application Platform 7
Red Hat
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-15561
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-15561
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:53644
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:53645
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:53646
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:53806
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:70228
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:70229
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