{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-15565", "assignerOrgId": "53f830b8-0a3f-465b-8143-3b8a9948e749", "state": "PUBLISHED", "assignerShortName": "redhat", "dateReserved": "2026-07-13T05:42:33.770Z", "datePublished": "2026-08-11T08:49:58.552Z", "dateUpdated": "2026-08-11T08:49:58.552Z"}, "containers": {"cna": {"title": "Undertow: undertow-websockets: undertow: pre-auth dos on websocket endpoint with @serverendpoint class with any @onmessage method", "metrics": [{"other": {"content": {"value": "Important", "namespace": "https://access.redhat.com/security/updates/classification/"}, "type": "Red Hat severity rating"}}, {"cvssV3_1": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 7.5, "baseSeverity": "HIGH", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}, "format": "CVSS"}], "descriptions": [{"lang": "en", "value": "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."}], "affected": [{"vendor": "Red Hat", "product": "Red Hat build of Apache Camel for Spring Boot 4", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "packageName": "undertow-websockets-jsr", "defaultStatus": "affected", "cpes": ["cpe:/a:redhat:camel_spring_boot:4"]}, {"vendor": "Red Hat", "product": "Red Hat Data Grid 8", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "packageName": "undertow-websockets-jsr", "defaultStatus": "affected", "cpes": ["cpe:/a:redhat:jboss_data_grid:8"]}, {"vendor": "Red Hat", "product": "Red Hat Fuse 7", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "packageName": "undertow-websockets-jsr", "defaultStatus": "unknown", "cpes": ["cpe:/a:redhat:jboss_fuse:7"]}, {"vendor": "Red Hat", "product": "Red Hat JBoss Enterprise Application Platform 7", "collectionURL": "https://access.redhat.com/jbossnetwork/restricted/listSoftware.html", "packageName": "undertow-websockets-jsr", "defaultStatus": "affected", "cpes": ["cpe:/a:redhat:jboss_enterprise_application_platform:7"]}, {"vendor": "Red Hat", "product": "Red Hat JBoss Enterprise Application Platform 8", "collectionURL": "https://access.redhat.com/jbossnetwork/restricted/listSoftware.html", "packageName": "undertow-websockets-jsr", "defaultStatus": "affected", "cpes": ["cpe:/a:redhat:jboss_enterprise_application_platform:8"]}, {"vendor": "Red Hat", "product": "Red Hat JBoss Enterprise Application Platform Expansion Pack", "collectionURL": "https://access.redhat.com/jbossnetwork/restricted/listSoftware.html", "packageName": "undertow-websockets-jsr", "defaultStatus": "unaffected", "cpes": ["cpe:/a:redhat:jbosseapxp"]}, {"vendor": "Red Hat", "product": "Red Hat Single Sign-On 7", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "packageName": "undertow-websockets-jsr", "defaultStatus": "unknown", "cpes": ["cpe:/a:redhat:red_hat_single_sign_on:7"]}], "references": [{"url": "https://access.redhat.com/security/cve/CVE-2026-15565", "tags": ["vdb-entry", "x_refsource_REDHAT"]}, {"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2490628", "name": "RHBZ#2490628", "tags": ["issue-tracking", "x_refsource_REDHAT"]}], "datePublic": "2026-08-11T05:55:42.770Z", "problemTypes": [{"descriptions": [{"cweId": "CWE-120", "description": "Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')", "lang": "en", "type": "CWE"}]}], "x_redhatCweChain": "CWE-120: Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')", "workarounds": [{"lang": "en", "value": "Option 1 \u2014 Server-wide configuration to disable websockets handshake:\n <!-- Remove <websockets/> from standalone.xml servlet-container -->\n <servlet-container name=\"default\">\n <jsp-config/>\n <!-- <websockets/> \u2190 remove this line entirely -->\n </servlet-container>\n isWebsocketsEnabled() returns false \u2192 no WebSocket upgrade accepted for any deployment.\n\nOption 2 \u2014 Per-application configuration to disable websockets handshake:\n <!-- WEB-INF/jboss-web.xml inside the WAR -->\n <jboss-web>\n <enable-websockets>false</enable-websockets>\n </jboss-web>\n Only that specific WAR's @ServerEndpoint classes are not registered."}], "timeline": [{"lang": "en", "time": "2026-06-19T00:58:08.395Z", "value": "Reported to Red Hat."}, {"lang": "en", "time": "2026-08-11T05:55:42.770Z", "value": "Made public."}], "providerMetadata": {"orgId": "53f830b8-0a3f-465b-8143-3b8a9948e749", "shortName": "redhat", "dateUpdated": "2026-08-11T08:49:58.552Z"}, "x_generator": {"engine": "cvelib 1.8.0"}}}}

{}

{"affected": [{"affectedData": [{"collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "cpes": ["cpe:/a:redhat:camel_spring_boot:4"], "defaultStatus": "affected", "packageName": "undertow-websockets-jsr", "product": "Red Hat build of Apache Camel for Spring Boot 4", "vendor": "Red Hat"}, {"collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "cpes": ["cpe:/a:redhat:jboss_data_grid:8"], "defaultStatus": "affected", "packageName": "undertow-websockets-jsr", "product": "Red Hat Data Grid 8", "vendor": "Red Hat"}, {"collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "cpes": ["cpe:/a:redhat:jboss_fuse:7"], "defaultStatus": "unknown", "packageName": "undertow-websockets-jsr", "product": "Red Hat Fuse 7", "vendor": "Red Hat"}, {"collectionURL": "https://access.redhat.com/jbossnetwork/restricted/listSoftware.html", "cpes": ["cpe:/a:redhat:jboss_enterprise_application_platform:7"], "defaultStatus": "affected", "packageName": "undertow-websockets-jsr", "product": "Red Hat JBoss Enterprise Application Platform 7", "vendor": "Red Hat"}, {"collectionURL": "https://access.redhat.com/jbossnetwork/restricted/listSoftware.html", "cpes": ["cpe:/a:redhat:jboss_enterprise_application_platform:8"], "defaultStatus": "affected", "packageName": "undertow-websockets-jsr", "product": "Red Hat JBoss Enterprise Application Platform 8", "vendor": "Red Hat"}, {"collectionURL": "https://access.redhat.com/jbossnetwork/restricted/listSoftware.html", "cpes": ["cpe:/a:redhat:jbosseapxp"], "defaultStatus": "unaffected", "packageName": "undertow-websockets-jsr", "product": "Red Hat JBoss Enterprise Application Platform Expansion Pack", "vendor": "Red Hat"}, {"collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "cpes": ["cpe:/a:redhat:red_hat_single_sign_on:7"], "defaultStatus": "unknown", "packageName": "undertow-websockets-jsr", "product": "Red Hat Single Sign-On 7", "vendor": "Red Hat"}], "source": "secalert@redhat.com"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "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."}], "id": "CVE-2026-15565", "lastModified": "2026-08-11T09:17:13.370", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 7.5, "baseSeverity": "HIGH", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 3.6, "source": "secalert@redhat.com", "type": "Primary"}]}, "published": "2026-08-11T09:17:13.370", "references": [{"source": "secalert@redhat.com", "url": "https://access.redhat.com/security/cve/CVE-2026-15565"}, {"source": "secalert@redhat.com", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2490628"}], "sourceIdentifier": "secalert@redhat.com", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-120"}], "source": "secalert@redhat.com", "type": "Primary"}]}

{"bugzilla": {"description": "undertow: undertow-websockets: Undertow: Pre-Auth DoS on websocket endpoint with @ServerEndpoint class with any @OnMessage method", "id": "2490628", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2490628"}, "csaw": false, "cvss3": {"cvss3_base_score": "7.5", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-120", "details": ["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."], "mitigation": {"lang": "en:us", "value": "Option 1 \u2014 Server-wide configuration to disable websockets handshake:\n<!-- Remove <websockets/> from standalone.xml servlet-container -->\n<servlet-container name=\"default\">\n<jsp-config/>\n<!-- <websockets/> \u2190 remove this line entirely -->\n</servlet-container>\nisWebsocketsEnabled() returns false \u2192 no WebSocket upgrade accepted for any deployment.\nOption 2 \u2014 Per-application configuration to disable websockets handshake:\n<!-- WEB-INF/jboss-web.xml inside the WAR -->\n<jboss-web>\n<enable-websockets>false</enable-websockets>\n</jboss-web>\nOnly that specific WAR's @ServerEndpoint classes are not registered."}, "name": "CVE-2026-15565", "package_state": [{"cpe": "cpe:/a:redhat:camel_spring_boot:4", "fix_state": "Affected", "package_name": "undertow-websockets-jsr", "product_name": "Red Hat build of Apache Camel for Spring Boot 4"}, {"cpe": "cpe:/a:redhat:jboss_data_grid:8", "fix_state": "Affected", "package_name": "undertow-websockets-jsr", "product_name": "Red Hat Data Grid 8"}, {"cpe": "cpe:/a:redhat:jboss_fuse:7", "fix_state": "Out of support scope", "package_name": "undertow-websockets-jsr", "product_name": "Red Hat Fuse 7"}, {"cpe": "cpe:/a:redhat:jboss_enterprise_application_platform:7", "fix_state": "Affected", "package_name": "undertow-websockets-jsr", "product_name": "Red Hat JBoss Enterprise Application Platform 7"}, {"cpe": "cpe:/a:redhat:jboss_enterprise_application_platform:8", "fix_state": "Affected", "package_name": "undertow-websockets-jsr", "product_name": "Red Hat JBoss Enterprise Application Platform 8"}, {"cpe": "cpe:/a:redhat:jbosseapxp", "fix_state": "Not affected", "package_name": "undertow-websockets-jsr", "product_name": "Red Hat JBoss Enterprise Application Platform Expansion Pack"}, {"cpe": "cpe:/a:redhat:red_hat_single_sign_on:7", "fix_state": "Out of support scope", "package_name": "undertow-websockets-jsr", "product_name": "Red Hat Single Sign-On 7"}], "public_date": "2026-08-11T05:55:42Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-15565\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-15565\nhttps://cwe.mitre.org/data/definitions/120.html"], "threat_severity": "Important"}

{"created": "2026-08-11T10:30:04.789012+00:00", "updated": "2026-08-11T10:30:04.789018+00:00", "vendors": []}