CVE-2026-15565
Undertow: undertow-websockets: undertow: pre-auth dos on websocket endpoint with @serverendpoint class with any @onmessage method
Description
A flaw was found in Undertow. A remote attacker can cause Out of Memory on websockets endpoint without authentication on any @ServerEndpoint class that has any @OnMessage method. This allows an attacker to cause Denial of Service attack without authentication and using only a standard WebSocket handshake.
No summary for this CVE yet.
CVSS Vector Breakdown
Exploitability
AV:NAttack VectorNetwork
AC:LAttack ComplexityLow
PR:NPrivileges RequiredNone
UI:NUser InteractionNone
Scope
S:UScopeUnchanged
Impact
C:NConfidentialityNone
I:NIntegrityNone
A:HAvailabilityHigh
Weaknesses
Affected Products
Red Hat
commercial·US
and 3 more affected products View all →
Exploitability
Workaround Available
Attack Graph
Products CVE Techniques Tactics
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MITRE ATT&CK
2 techniques Initial Access
Privilege Escalation
References
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
and 6 more references View all →
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