VDB

CVE-2026-15565

CVE-2026-15565 PUBLISHED CVSS 7.5 HIGH

Reported by redhat · Published August 11, 2026

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.

Risk scores

CVSS 3.1
7.5
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected products

VendorProductVersions
Red HatRed Hat JBoss Enterprise Application Platform 7.4.25
Red HatRed Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 70:2.16.0-22.redhat_00057.1.el7eap
Red HatRed Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 70:2.3.14-11.SP11_redhat_00001.1.el7eap
Red HatRed Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 70:1.5.26-2.Final_redhat_00001.1.el7eap
Red HatRed Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 70:2.18.8-1.redhat_00003.1.el7eap
Red HatRed Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 70:2.18.8-1.redhat_00003.1.el7eap
Red HatRed Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 70:2.18.8-1.redhat_00003.1.el7eap
Red HatRed Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 70:2.18.8-1.redhat_00003.1.el7eap
Red HatRed Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 70:2.18.8-1.redhat_00003.1.el7eap
Red HatRed Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 70:2.18.8-1.redhat_00003.1.el7eap
Red HatRed Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 70:5.0.31-3.SP2_redhat_00001.1.el7eap
Red HatRed Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 70:1.10.0-46.Final_redhat_00044.1.el7eap
Red HatRed Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 70:4.1.135-1.Final_redhat_00001.1.el7eap
Red HatRed Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 70:4.1.135-1.Final_redhat_00001.1.el7eap
Red HatRed Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 70:2.5.5-30.SP12_redhat_00020.1.el7eap
Red HatRed Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 70:2.5.5-24.SP12_redhat_00016.1.el7eap
Red HatRed Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 70:2.2.40-2.SP3_redhat_00001.1.el7eap
Red HatRed Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 70:7.4.25-2.GA_redhat_00001.1.el7eap
Red HatRed Hat JBoss Enterprise Application Platform 8.1.8.GA2.3.26.SP3-redhat-00001
Red HatRed Hat JBoss Enterprise Application Platform 8.1 for RHEL 100:2.40.0-8.redhat_00024.1.el10eap

…and 314 more

Timeline

  • Aug 11, 2026 EPSS Score (28 in total, the first dated here)
  • Aug 11, 2026 Coalition ESS Score
  • Aug 11, 2026 CVE Published
  • Aug 16, 2026 Security Advisory (9 in total, the first dated here)
  • Sep 22, 2026 Distribution Patch (8 in total, the first dated here)
  • Nov 1, 2026 CVE Updated

Query this with the API

The same record, from the CLI:

vulnetix vdb vuln CVE-2026-15565
vulnetix vdb fixes CVE-2026-15565

Or with curl, using the org id and key from your account page:

curl -s -H "Authorization: ApiKey ${VULNETIX_ORG_ID}:${VULNETIX_API_KEY}" \
  "https://api.vdb.vulnetix.com/v2/vuln/CVE-2026-15565/fixes/registry"

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References

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