CVE-2026-5680

Description

A flaw was found in Undertow. A remote attacker could exploit this vulnerability by sending specially crafted WebSocket messages with permessage-deflate negotiated. This could lead to excessive memory consumption due to the PerMessageDeflateFunction.largerBuffer() method using exponential doubling, resulting in a Denial of Service (DoS) for the affected application.

CVSS Vector

References

• https://access.redhat.com/security/cve/CVE-2026-5680
• https://bugzilla.redhat.com/show_bug.cgi?id=2455350