CVE-2026-5680 Undertow-core: undertow: denial of service via websocket permessage-deflate processing

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,...

CVE-2026-15561 Undertow-core: oom via missing limits in chunked trailer in eap's undertow

A flaw was found in EAP's undertow http/1.1 chunked-transfer decoder. missing limits on size and count would allow an attacker to use an unauthenticated connection to drive the JVM to an OutOfMemory error, stopping all deployments on the listener, and achieving Denial of Service...

CVE-2026-15561 Undertow-core: oom via missing limits in chunked trailer in eap's undertow

A flaw was found in EAP's undertow http/1.1 chunked-transfer decoder. missing limits on size and count would allow an attacker to use an unauthenticated connection to drive the JVM to an OutOfMemory error, stopping all deployments on the listener, and achieving Denial of Service...

undertow-core: Undertow HTTP Server Fails to Reject Malformed Host Headers Leading to Potential Cache Poisoning and SSRF

A flaw was found in the Undertow HTTP server core, which is used in WildFly, JBoss EAP, and other Java applications. The Undertow library fails to properly validate the Host header in incoming HTTP requests.As a result, requests containing malformed or malicious Host headers are processed without...

HTTP Request Smuggling

Overview io.undertow:undertow-core is a Java web server based on non-blocking IO. Affected versions of this package are vulnerable to HTTP Request Smuggling via discrepancies in the parsing of HTTP header names. An attacker can bypass security controls and access unauthorized resources by sending...

HTTP Request Smuggling

Overview io.undertow:undertow-core is a Java web server based on non-blocking IO. Affected versions of this package are vulnerable to HTTP Request Smuggling due to incorrect handling of white-spaces in HTTP request headers. An attacker can gain unauthorized access to restricted information or...

HTTP Request Smuggling

Overview io.undertow:undertow-core is a Java web server based on non-blocking IO. Affected versions of this package are vulnerable to HTTP Request Smuggling via the proxy server. An attacker can gain unauthorized access or manipulate web requests by sending specially crafted header block...

Allocation of Resources Without Limits or Throttling

Overview io.undertow:undertow-core is a Java web server based on non-blocking IO. Affected versions of this package are vulnerable to Allocation of Resources Without Limits or Throttling via the MultiPartParserDefinition multipart parsing process in MultiPartParserDefinition.java. An attacker can...

undertow-core: Undertow HTTP Server Fails to Reject Malformed Host Headers Leading to Potential Cache Poisoning and SSRF

A flaw was found in the Undertow HTTP server core, which is used in WildFly, JBoss EAP, and other Java applications. The Undertow library fails to properly validate the Host header in incoming HTTP requests.As a result, requests containing malformed or malicious Host headers are processed without...

Important: Red Hat Security Advisory: Red Hat JBoss Enterprise Application Platform 7.4.24 security update

A security update is now available for Red Hat JBoss Enterprise Application Platform 7.4 for Red Hat Enterprise Linux 7. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System CVSS base score, which gives a detailed severity...

undertow-core: Undertow HTTP Server Fails to Reject Malformed Host Headers Leading to Potential Cache Poisoning and SSRF

A flaw was found in the Undertow HTTP server core, which is used in WildFly, JBoss EAP, and other Java applications. The Undertow library fails to properly validate the Host header in incoming HTTP requests.As a result, requests containing malformed or malicious Host headers are processed without...

Important: Red Hat Security Advisory: Red Hat JBoss Enterprise Application Platform 8.0.12 security update

A security update is now available for Red Hat JBoss Enterprise Application Platform 8.0. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System CVSS base score, which gives a detailed severity rating, is available for each...

undertow-core: Undertow HTTP Server Fails to Reject Malformed Host Headers Leading to Potential Cache Poisoning and SSRF

A flaw was found in the Undertow HTTP server core, which is used in WildFly, JBoss EAP, and other Java applications. The Undertow library fails to properly validate the Host header in incoming HTTP requests.As a result, requests containing malformed or malicious Host headers are processed without...

Allocation of Resources Without Limits or Throttling

Overview io.undertow:undertow-core is a Java web server based on non-blocking IO. Affected versions of this package are vulnerable to Allocation of Resources Without Limits or Throttling via the getParameterNames function. An attacker can cause an OutOfMemoryError by sending requests with...

Undertow-core: undertow http server fails to reject malformed host headers leading to potential cache poisoning and ssrf (CVE-2025-12543)

A flaw was found in the Undertow HTTP server core, which is used in WildFly, JBoss EAP, and other Java applications. The Undertow library fails to properly validate the Host header in incoming HTTP requests. As a result, requests containing malformed or malicious Host headers are processed withou...

undertow-core: Undertow HTTP Server Fails to Reject Malformed Host Headers Leading to Potential Cache Poisoning and SSRF

A flaw was found in the Undertow HTTP server core, which is used in WildFly, JBoss EAP, and other Java applications. The Undertow library fails to properly validate the Host header in incoming HTTP requests.As a result, requests containing malformed or malicious Host headers are processed without...

Improper Validation of Syntactic Correctness of Input

Overview io.undertow:undertow-core is a Java web server based on non-blocking IO. Affected versions of this package are vulnerable to Improper Validation of Syntactic Correctness of Input of the request's Host header. An attacker can manipulate server behavior, potentially leading to cache...

CVE-2025-12543

Undertow core in WildFly/JBoss EAP is affected by CVE-2025-12543 due to improper validation of the Host header in HTTP requests. This can allow cache poisoning, internal network discovery, or user session hijacking. The CVSSv3.1 base score is 9.6 (CRITICAL) with network access, low attack complex...

CVE-2025-12543 Undertow-core: undertow http server fails to reject malformed host headers leading to potential cache poisoning and ssrf

A flaw was found in the Undertow HTTP server core, which is used in WildFly, JBoss EAP, and other Java applications. The Undertow library fails to properly validate the Host header in incoming HTTP requests.As a result, requests containing malformed or malicious Host headers are processed without...

Allocation of Resources Without Limits or Throttling

Overview io.undertow:undertow-core is a Java web server based on non-blocking IO. Affected versions of this package are vulnerable to Allocation of Resources Without Limits or Throttling when parsing multipart uploads, which apply the UndertowOptions.MULTIPARTMAXENTITYSIZE option. An attacker can...