GHSA-6HR6-W5QG-QMWG h2: Duplicate Host header could facilitate request smuggling

Impact h2 =4.4.0 accepts request header blocks containing more than one Host header, and forwards every Host header to the consuming application. Where the consumer downgrades HTTP/2 to HTTP/1.1, the resulting request carries two Host header lines, which is a request smuggling primitive CWE-444...

h2: Duplicate Host header could facilitate request smuggling

Impact h2 =4.4.0 accepts request header blocks containing more than one Host header, and forwards every Host header to the consuming application. Where the consumer downgrades HTTP/2 to HTTP/1.1, the resulting request carries two Host header lines, which is a request smuggling primitive CWE-444...

HTTP Request Smuggling

Overview h2 is a Pure-Python HTTP/2 protocol implementation Affected versions of this package are vulnerable to HTTP Request Smuggling via the processing of HTTP/2 request headers containing multiple Host headers. An attacker can interfere with downstream HTTP/1.1 applications by crafting request...

EUVD-2026-54177

h2 is a pure-Python implementation of a HTTP/2 protocol stack. Versions up to and including 4.4.0 accept request header blocks containing more than one Host header, and forward every Host header to the consuming application. Where the consumer downgrades HTTP/2 to HTTP/1.1, the resulting request...

CVE-2026-71554 h2: Duplicate Host header could facilitate request smuggling

h2 is a pure-Python implementation of a HTTP/2 protocol stack. Versions up to and including 4.4.0 accept request header blocks containing more than one Host header, and forward every Host header to the consuming application. Where the consumer downgrades HTTP/2 to HTTP/1.1, the resulting request...

CVE-2026-71554

CVE-2026-71554 affects the Python HTTP/2 stack in the h2 package. Versions up to and including 4.4.0 accept header blocks containing more than one Host header and forward all Host headers to the application. When a client downgrades HTTP/2 to HTTP/1.1, this can yield two Host header lines, enabli...

CVE-2026-71554 h2: Duplicate Host header could facilitate request smuggling

h2 is a pure-Python implementation of a HTTP/2 protocol stack. Versions up to and including 4.4.0 accept request header blocks containing more than one Host header, and forward every Host header to the consuming application. Where the consumer downgrades HTTP/2 to HTTP/1.1, the resulting request...

SUSE CVE-2026-67181

Rouille 0.3.3 through 3.6.2 contains an HTTP request smuggling vulnerability that allows remote attackers to desynchronize HTTP message boundaries by exploiting improper header forwarding in the proxy implementation. The proxy in src/proxy.rs forwards the client's Transfer-Encoding header to...

PT-2026-68817

Name of the Vulnerable Software and Affected Versions h2 versions prior to 4.4.1 Description The software accepts request header blocks containing multiple Host headers and forwards all of them to the consuming application. When the consumer downgrades the connection from HTTP/2 to HTTP/1.1, the...

CVE-2026-9190

An HTTP request smuggling vulnerability in the HTTP App Server of Progress MarkLogic Server before 11.3.6 and 12.0.3 allows a remote attacker to bypass authentication and authorization checks, hijack a legitimate user's session, or capture credentials. The vulnerability occurs when a crafted HTTP...

CVE-2026-9190

Progress MarkLogic Server versions before 11.3.6 and 12.0.3 contain an HTTP request smuggling flaw in the HTTP App Server. A crafted request with both Content-Length and Transfer-Encoding headers can cause the reverse proxy and MarkLogic Server to misinterpret request boundaries, enabling an atta...

CVE-2026-9190 HTTP request smuggling in Progress MarkLogic Server

An HTTP request smuggling vulnerability in the HTTP App Server of Progress MarkLogic Server before 11.3.6 and 12.0.3 allows a remote attacker to bypass authentication and authorization checks, hijack a legitimate user's session, or capture credentials. The vulnerability occurs when a crafted HTTP...

CRLF Injection

undici is vulnerable to CRLF Injection. The vulnerability is due to undici not validating the type property of a duck-typed blob-like request body before using it as the Content-Type header on the HTTP/1.1 dispatcher, where an attacker can inject CRLF sequences and append arbitrary HTTP headers,...

SUSE CVE-2026-69243

AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to 3.14.2, the HTTP parsers were vulnerable to a request smuggling attack relating to WebSocket upgrades. If using the server-side component, an attacker may be able to execute a request smuggling vulnerability...

PT-2026-68218

Name of the Vulnerable Software and Affected Versions Progress MarkLogic Server versions prior to 11.3.6 Progress MarkLogic Server versions prior to 12.0.3 Description An HTTP request smuggling issue exists in the HTTP App Server. This occurs when a crafted HTTP request containing both...

CVE-2026-15157

A flaw was found in undici. An application that processes a hand-rolled blob-like request body with a type property derived from untrusted input may allow a remote attacker to inject Carriage Return Line Feed CRLF sequences. This vulnerability enables the attacker to append arbitrary HTTP headers...

Inconsistent Interpretation of HTTP Requests at org.eclipse.jetty:jetty-http dependency in Crucible Server

This is a vulnerability in a non-Atlassian Crucible Server dependency. Atlassian's application of this dependency presents a lower, non-critical assessed risk. This Critical severity Inconsistent Interpretation of HTTP Requests vulnerability was introduced in version 4.9.0 of Crucible Server. Thi...

org.eclipse.jetty/jetty-http: HTTP request smuggling via chunked extension quoted-string parsing

A flaw was found in Eclipse Jetty. The HTTP/1.1 parser is vulnerable to request smuggling when chunk extensions are used. An attacker can inject crafted requests to manipulate and trick the parser. This issue can lead to security controls bypass, cache poisoning or unauthorized endpoint access...

org.eclipse.jetty/jetty-http: HTTP request smuggling via chunked extension quoted-string parsing

A flaw was found in Eclipse Jetty. The HTTP/1.1 parser is vulnerable to request smuggling when chunk extensions are used. An attacker can inject crafted requests to manipulate and trick the parser. This issue can lead to security controls bypass, cache poisoning or unauthorized endpoint access...

org.eclipse.jetty/jetty-http: HTTP request smuggling via chunked extension quoted-string parsing

A flaw was found in Eclipse Jetty. The HTTP/1.1 parser is vulnerable to request smuggling when chunk extensions are used. An attacker can inject crafted requests to manipulate and trick the parser. This issue can lead to security controls bypass, cache poisoning or unauthorized endpoint access...