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 (200)
page 2 of 10| CVE | Vendor / Product | Sev | Risk | CVSS | EPSS | KEV | Published | Description |
|---|---|---|---|---|---|---|---|---|
| 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-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-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-2026-31842 | 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-2024-44775 | Hig | 0.49 | 7.5 | 0.01 | Oct 15, 2024 | kmqtt v0.2.7 is vulnerable to Denial of Service (DoS) due to a Null Pointer Exception. A remote attacker can cause the broker to crash by sending a specially crafted MQTT CONNECT packet that triggers an unhandled null reference, leading to an immediate process termination. | ||
| CVE-2018-3908 | Hig | 0.49 | 7.5 | 0.01 | Aug 28, 2018 | An exploitable vulnerability exists in the REST parser of video-core's HTTP server of the Samsung SmartThings Hub STH-ETH-250-Firmware version 0.20.17. The video-core process incorrectly handles pipelined HTTP requests, which allows successive requests to overwrite the… | ||
| CVE-2017-7656 | Hig | 0.49 | 7.5 | 0.06 | Jun 26, 2018 | In Eclipse Jetty, versions 9.2.x and older, 9.3.x (all configurations), and 9.4.x (non-default configuration with RFC2616 compliance enabled), HTTP/0.9 is handled poorly. An HTTP/1 style request line (i.e. method space URI space version) that declares a version of HTTP/0.9 was… | ||
| CVE-2017-7561 | Hig | 0.49 | 7.5 | 0.02 | Sep 13, 2017 | Red Hat JBoss EAP version 3.0.7 through before 4.0.0.Beta1 is vulnerable to a server-side cache poisoning or CORS requests in the JAX-RS component resulting in a moderate impact. | ||
| CVE-2026-2332 | Hig | 0.48 | 7.4 | 0.01 | Apr 14, 2026 | In Eclipse Jetty, the HTTP/1.1 parser is vulnerable to request smuggling when chunk extensions are used, similar to the "funky chunks" techniques outlined here: * https://w4ke.info/2025/06/18/funky-chunks.html * https://w4ke.info/2025/10/29/funky-chunks-2.html Jetty… | ||
| CVE-2026-42584 | Hig | 0.47 | 7.3 | 0.01 | May 13, 2026 | Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final and 4.1.133.Final, HttpClientCodec pairs each inbound response with an outbound request by queue.poll() once per response, including for 1xx. If the client pipelines GET then HEAD and the… | ||
| CVE-2024-41671 | Hig | 0.47 | 8.3 | 0.01 | Jul 29, 2024 | Twisted is an event-based framework for internet applications, supporting Python 3.6+. The HTTP 1.0 and 1.1 server provided by twisted.web could process pipelined HTTP requests out-of-order, possibly resulting in information disclosure. This vulnerability is fixed in 24.7.0rc1. | ||
| CVE-2025-12811 | Med | 0.45 | — | 0.00 | Feb 18, 2026 | Improper Inconsistent Interpretation of HTTP Requests ('HTTP Request Smuggling') in Delinea Inc. Cloud Suite and Privileged Access Service. If you're not using the latest Server Suite agents, this fix requires that you upgrade to Server Suite 2023.1 (agent 6.0.1) or later. * … | ||
| CVE-2025-41082 | Med | 0.45 | — | 0.00 | Jan 26, 2026 | Illegal HTTP request traffic vulnerability (CL.0) in Altitude Communication Server, caused by inconsistent analysis of multiple HTTP requests over a single Keep-Alive connection using Content-Length headers. This can cause a desynchronization of requests between frontend and… | ||
| CVE-2023-53878 | Med | 0.45 | — | 0.00 | Dec 15, 2025 | Member Login Script 3.3 contains a client-side desynchronization vulnerability that allows attackers to manipulate HTTP request handling by exploiting Content-Length header parsing. Attackers can send crafted POST requests with smuggled secondary requests to potentially bypass… | ||
| CVE-2025-11915 | — | Med | 0.45 | — | 0.00 | Oct 22, 2025 | Connection desynchronization between an HTTP proxy and the model backend. The fixes were rolled out for all proxies in front of impacted models by 2025-09-28. Users do not need to take any action. |
- 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 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 0.49cvss 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 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
kmqtt v0.2.7 is vulnerable to Denial of Service (DoS) due to a Null Pointer Exception. A remote attacker can cause the broker to crash by sending a specially crafted MQTT CONNECT packet that triggers an unhandled null reference, leading to an immediate process termination.
- risk 0.49cvss 7.5epss 0.01
An exploitable vulnerability exists in the REST parser of video-core's HTTP server of the Samsung SmartThings Hub STH-ETH-250-Firmware version 0.20.17. The video-core process incorrectly handles pipelined HTTP requests, which allows successive requests to overwrite the…
- risk 0.49cvss 7.5epss 0.06
In Eclipse Jetty, versions 9.2.x and older, 9.3.x (all configurations), and 9.4.x (non-default configuration with RFC2616 compliance enabled), HTTP/0.9 is handled poorly. An HTTP/1 style request line (i.e. method space URI space version) that declares a version of HTTP/0.9 was…
- risk 0.49cvss 7.5epss 0.02
Red Hat JBoss EAP version 3.0.7 through before 4.0.0.Beta1 is vulnerable to a server-side cache poisoning or CORS requests in the JAX-RS component resulting in a moderate impact.
- risk 0.48cvss 7.4epss 0.01
In Eclipse Jetty, the HTTP/1.1 parser is vulnerable to request smuggling when chunk extensions are used, similar to the "funky chunks" techniques outlined here: * https://w4ke.info/2025/06/18/funky-chunks.html * https://w4ke.info/2025/10/29/funky-chunks-2.html Jetty…
- risk 0.47cvss 7.3epss 0.01
Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final and 4.1.133.Final, HttpClientCodec pairs each inbound response with an outbound request by queue.poll() once per response, including for 1xx. If the client pipelines GET then HEAD and the…
- risk 0.47cvss 8.3epss 0.01
Twisted is an event-based framework for internet applications, supporting Python 3.6+. The HTTP 1.0 and 1.1 server provided by twisted.web could process pipelined HTTP requests out-of-order, possibly resulting in information disclosure. This vulnerability is fixed in 24.7.0rc1.
- risk 0.45cvss —epss 0.00
Improper Inconsistent Interpretation of HTTP Requests ('HTTP Request Smuggling') in Delinea Inc. Cloud Suite and Privileged Access Service. If you're not using the latest Server Suite agents, this fix requires that you upgrade to Server Suite 2023.1 (agent 6.0.1) or later. * …
- risk 0.45cvss —epss 0.00
Illegal HTTP request traffic vulnerability (CL.0) in Altitude Communication Server, caused by inconsistent analysis of multiple HTTP requests over a single Keep-Alive connection using Content-Length headers. This can cause a desynchronization of requests between frontend and…
- risk 0.45cvss —epss 0.00
Member Login Script 3.3 contains a client-side desynchronization vulnerability that allows attackers to manipulate HTTP request handling by exploiting Content-Length header parsing. Attackers can send crafted POST requests with smuggled secondary requests to potentially bypass…
- risk 0.45cvss —epss 0.00
Connection desynchronization between an HTTP proxy and the model backend. The fixes were rolled out for all proxies in front of impacted models by 2025-09-28. Users do not need to take any action.