CWE-444
Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')
Description
The product acts as an intermediary HTTP agent (such as a proxy or firewall) in the data flow between two entities such as a client and server, but it does not interpret malformed HTTP requests or responses in ways that are consistent with how the messages will be processed by those entities that are at the ultimate destination.
Hierarchy (View 1000)
Parents
Children
none
Related attack patterns (CAPEC)
CAPEC-273 · CAPEC-33
CVEs mapped to this weakness (386)
page 5 of 20| CVE | Vendor / Product | Sev | Risk | CVSS | EPSS | KEV | Published | Description |
|---|---|---|---|---|---|---|---|---|
| CVE-2025-58068 | Cri | 0.52 | 9.1 | 0.00 | Aug 29, 2025 | Eventlet is a concurrent networking library for Python. Prior to version 0.40.3, the Eventlet WSGI parser is vulnerable to HTTP Request Smuggling due to improper handling of HTTP trailer sections. This vulnerability could enable attackers to, bypass front-end security controls,… | ||
| CVE-2025-43859 | Cri | 0.52 | 9.1 | 0.01 | Apr 24, 2025 | h11 is a Python implementation of HTTP/1.1. Prior to version 0.16.0, a leniency in h11's parsing of line terminators in chunked-coding message bodies can lead to request smuggling vulnerabilities under certain conditions. This issue has been patched in version 0.16.0. Since… | ||
| CVE-2025-22871 | Cri | 0.52 | 9.1 | 0.01 | Apr 8, 2025 | The net/http package improperly accepts a bare LF as a line terminator in chunked data chunk-size lines. This can permit request smuggling if a net/http server is used in conjunction with a server that incorrectly accepts a bare LF as part of a chunk-ext. | ||
| CVE-2024-49768 | Cri | 0.52 | 9.1 | 0.00 | Oct 29, 2024 | Waitress is a Web Server Gateway Interface server for Python 2 and 3. A remote client may send a request that is exactly recv_bytes (defaults to 8192) long, followed by a secondary request using HTTP pipelining. When request lookahead is disabled (default) we won't read any more… | ||
| CVE-2022-24790 | Cri | 0.52 | 9.1 | 0.02 | Mar 30, 2022 | Puma is a simple, fast, multi-threaded, parallel HTTP 1.1 server for Ruby/Rack applications. When using Puma behind a proxy that does not properly validate that the incoming HTTP request matches the RFC7230 standard, Puma and the frontend proxy may disagree on where a request… | ||
| CVE-2017-15643 | Hig | 0.52 | 7.4 | 0.06 | Oct 19, 2017 | An active network attacker (MiTM) can achieve remote code execution on a machine that runs IKARUS Anti Virus 2.16.7. IKARUS AV for Windows uses cleartext HTTP for updates along with a CRC32 checksum and an update value for verification of the downloaded files. The attacker first… | ||
| CVE-2026-23527 | — | Hig | 0.51 | 8.9 | 0.01 | Jan 15, 2026 | H3 is a minimal H(TTP) framework built for high performance and portability. Prior to 1.15.5, there is a critical HTTP Request Smuggling vulnerability. readRawBody is doing a strict case-sensitive check for the Transfer-Encoding header. It explicitly looks for "chunked", but per… | |
| CVE-2026-28369 | Hig | 0.50 | 8.7 | 0.01 | Mar 27, 2026 | A flaw was found in Undertow. When Undertow receives an HTTP request where the first header line starts with one or more spaces, it incorrectly processes the request by stripping these leading spaces. This behavior, which violates HTTP standards, can be exploited by a remote… | ||
| CVE-2026-28368 | Hig | 0.50 | 8.7 | 0.01 | Mar 27, 2026 | A flaw was found in Undertow. This vulnerability allows a remote attacker to construct specially crafted requests where header names are parsed differently by Undertow compared to upstream proxies. This discrepancy in header interpretation can be exploited to launch request… | ||
| CVE-2026-28367 | Hig | 0.50 | 8.7 | 0.01 | Mar 27, 2026 | A flaw was found in Undertow. A remote attacker can exploit this vulnerability by sending `\r\r\r` as a header block terminator. This can be used for request smuggling with certain proxy servers, such as older versions of Apache Traffic Server and Google Cloud Classic… | ||
| CVE-2024-33452 | Hig | 0.50 | 7.7 | 0.01 | Apr 22, 2025 | An issue in OpenResty lua-nginx-module v.0.10.26 and before allows a remote attacker to conduct HTTP request smuggling via a crafted HEAD request. | ||
| CVE-2022-26377 | Hig | 0.50 | 7.5 | 0.20 | Jun 9, 2022 | Inconsistent Interpretation of HTTP Requests ('HTTP Request Smuggling') vulnerability in mod_proxy_ajp of Apache HTTP Server allows an attacker to smuggle requests to the AJP server it forwards requests to. This issue affects Apache HTTP Server Apache HTTP Server 2.4 version… | ||
| CVE-2026-59898 | Hig | 0.49 | 7.5 | 0.00 | Jul 29, 2026 | Netty is an asynchronous, event-driven network application framework. Prior to versions 4.1.136.Final and 4.2.16.Final, ab attacker can force WebSocket upgrade via the lax V07 (or V08) handshaker by sending `Sec-WebSocket-Version: 7` and omitting `Connection: Upgrade` /… | ||
| CVE-2026-67182 | Hig | 0.49 | 7.5 | 0.00 | Jul 28, 2026 | Rouille 0.3.3 through 3.6.2 contains an HTTP request smuggling vulnerability that allows remote attackers to bypass access controls by injecting bare line feed characters (0x0A) into client-supplied request header values that are copied verbatim to upstream connections without… | ||
| CVE-2025-3110 | Hig | 0.49 | 7.5 | 0.00 | Jul 8, 2026 | OpenVPN Access Server 2.7.2 through 3.1.0 accepts bare line-feed sequences inside HTTP header values, allowing remote attackers to perform HTTP request smuggling when deployed behind a reverse proxy | ||
| CVE-2026-8620 | Hig | 0.49 | 7.5 | 0.00 | May 26, 2026 | IBM Web Server Plug-ins for WebSphere Application Server and WebSphere Liberty 8.5, 9.0 IBM WebSphere Application Server and WebSphere Application Server Liberty are vulnerable to HTTP request smuggling in the Web Server Plug-ins through a specially crafted request. | ||
| CVE-2026-40562 | Hig | 0.49 | 7.5 | 0.00 | May 6, 2026 | Gazelle versions through 0.49 for Perl allows HTTP Request Smuggling via Improper Header Precedence. Gazelle incorrectly prioritizes "Content-Length" over "Transfer-Encoding: chunked" when both headers are present in an HTTP request. Per RFC 7230 3.3.3, Transfer-Encoding must… | ||
| CVE-2026-33805 | Hig | 0.49 | 8.6 | 0.00 | Apr 15, 2026 | @fastify/reply-from v12.6.1 and earlier and @fastify/http-proxy v11.4.3 and earlier process the client's Connection header after the proxy has added its own headers via rewriteRequestHeaders. This allows attackers to retroactively strip proxy-added headers from upstream requests… | ||
| CVE-2026-31842 | Hig | 0.49 | 7.5 | 0.01 | Apr 7, 2026 | Tinyproxy through 1.11.3 is vulnerable to HTTP request parsing desynchronization due to a case-sensitive comparison of the Transfer-Encoding header in src/reqs.c. The is_chunked_transfer function uses strcmp to compare the header value against "chunked", even though RFC 7230… | ||
| CVE-2025-61258 | Hig | 0.49 | 7.5 | 0.01 | Dec 9, 2025 | Outsystems Platform Server 11.18.1.37828 allows attackers to cause a denial of service via a crafted content-length value mismatching the body length. NOTE: the Supplier indicates that they are unable to reproduce this. |
- risk 0.52cvss 9.1epss 0.00
Eventlet is a concurrent networking library for Python. Prior to version 0.40.3, the Eventlet WSGI parser is vulnerable to HTTP Request Smuggling due to improper handling of HTTP trailer sections. This vulnerability could enable attackers to, bypass front-end security controls,…
- risk 0.52cvss 9.1epss 0.01
h11 is a Python implementation of HTTP/1.1. Prior to version 0.16.0, a leniency in h11's parsing of line terminators in chunked-coding message bodies can lead to request smuggling vulnerabilities under certain conditions. This issue has been patched in version 0.16.0. Since…
- risk 0.52cvss 9.1epss 0.01
The net/http package improperly accepts a bare LF as a line terminator in chunked data chunk-size lines. This can permit request smuggling if a net/http server is used in conjunction with a server that incorrectly accepts a bare LF as part of a chunk-ext.
- risk 0.52cvss 9.1epss 0.00
Waitress is a Web Server Gateway Interface server for Python 2 and 3. A remote client may send a request that is exactly recv_bytes (defaults to 8192) long, followed by a secondary request using HTTP pipelining. When request lookahead is disabled (default) we won't read any more…
- risk 0.52cvss 9.1epss 0.02
Puma is a simple, fast, multi-threaded, parallel HTTP 1.1 server for Ruby/Rack applications. When using Puma behind a proxy that does not properly validate that the incoming HTTP request matches the RFC7230 standard, Puma and the frontend proxy may disagree on where a request…
- risk 0.52cvss 7.4epss 0.06
An active network attacker (MiTM) can achieve remote code execution on a machine that runs IKARUS Anti Virus 2.16.7. IKARUS AV for Windows uses cleartext HTTP for updates along with a CRC32 checksum and an update value for verification of the downloaded files. The attacker first…
- risk 0.51cvss 8.9epss 0.01
H3 is a minimal H(TTP) framework built for high performance and portability. Prior to 1.15.5, there is a critical HTTP Request Smuggling vulnerability. readRawBody is doing a strict case-sensitive check for the Transfer-Encoding header. It explicitly looks for "chunked", but per…
- risk 0.50cvss 8.7epss 0.01
A flaw was found in Undertow. When Undertow receives an HTTP request where the first header line starts with one or more spaces, it incorrectly processes the request by stripping these leading spaces. This behavior, which violates HTTP standards, can be exploited by a remote…
- risk 0.50cvss 8.7epss 0.01
A flaw was found in Undertow. This vulnerability allows a remote attacker to construct specially crafted requests where header names are parsed differently by Undertow compared to upstream proxies. This discrepancy in header interpretation can be exploited to launch request…
- risk 0.50cvss 8.7epss 0.01
A flaw was found in Undertow. A remote attacker can exploit this vulnerability by sending `\r\r\r` as a header block terminator. This can be used for request smuggling with certain proxy servers, such as older versions of Apache Traffic Server and Google Cloud Classic…
- risk 0.50cvss 7.7epss 0.01
An issue in OpenResty lua-nginx-module v.0.10.26 and before allows a remote attacker to conduct HTTP request smuggling via a crafted HEAD request.
- risk 0.50cvss 7.5epss 0.20
Inconsistent Interpretation of HTTP Requests ('HTTP Request Smuggling') vulnerability in mod_proxy_ajp of Apache HTTP Server allows an attacker to smuggle requests to the AJP server it forwards requests to. This issue affects Apache HTTP Server Apache HTTP Server 2.4 version…
- risk 0.49cvss 7.5epss 0.00
Netty is an asynchronous, event-driven network application framework. Prior to versions 4.1.136.Final and 4.2.16.Final, ab attacker can force WebSocket upgrade via the lax V07 (or V08) handshaker by sending `Sec-WebSocket-Version: 7` and omitting `Connection: Upgrade` /…
- risk 0.49cvss 7.5epss 0.00
Rouille 0.3.3 through 3.6.2 contains an HTTP request smuggling vulnerability that allows remote attackers to bypass access controls by injecting bare line feed characters (0x0A) into client-supplied request header values that are copied verbatim to upstream connections without…
- risk 0.49cvss 7.5epss 0.00
OpenVPN Access Server 2.7.2 through 3.1.0 accepts bare line-feed sequences inside HTTP header values, allowing remote attackers to perform HTTP request smuggling when deployed behind a reverse proxy
- risk 0.49cvss 7.5epss 0.00
IBM Web Server Plug-ins for WebSphere Application Server and WebSphere Liberty 8.5, 9.0 IBM WebSphere Application Server and WebSphere Application Server Liberty are vulnerable to HTTP request smuggling in the Web Server Plug-ins through a specially crafted request.
- risk 0.49cvss 7.5epss 0.00
Gazelle versions through 0.49 for Perl allows HTTP Request Smuggling via Improper Header Precedence. Gazelle incorrectly prioritizes "Content-Length" over "Transfer-Encoding: chunked" when both headers are present in an HTTP request. Per RFC 7230 3.3.3, Transfer-Encoding must…
- risk 0.49cvss 8.6epss 0.00
@fastify/reply-from v12.6.1 and earlier and @fastify/http-proxy v11.4.3 and earlier process the client's Connection header after the proxy has added its own headers via rewriteRequestHeaders. This allows attackers to retroactively strip proxy-added headers from upstream requests…
- risk 0.49cvss 7.5epss 0.01
Tinyproxy through 1.11.3 is vulnerable to HTTP request parsing desynchronization due to a case-sensitive comparison of the Transfer-Encoding header in src/reqs.c. The is_chunked_transfer function uses strcmp to compare the header value against "chunked", even though RFC 7230…
- risk 0.49cvss 7.5epss 0.01
Outsystems Platform Server 11.18.1.37828 allows attackers to cause a denial of service via a crafted content-length value mismatching the body length. NOTE: the Supplier indicates that they are unable to reproduce this.