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 18 of 20| CVE | Vendor / Product | Sev | Risk | CVSS | EPSS | KEV | Published | Description |
|---|---|---|---|---|---|---|---|---|
| CVE-2026-44546 | Low | 0.24 | 3.7 | 0.00 | Jun 3, 2026 | daphne before 4.2.2 reconstructs a raw HTTP request from Twisted's parsed headers and feeds it to autobahn for WebSocket handshake processing. Twisted does not treat \x0b, \x0c, \x1c, \x1d, \x1e, or \x85 as header line separators, but autobahn decodes header values to str and… | ||
| CVE-2026-2708 | Low | 0.24 | 3.7 | 0.00 | Apr 23, 2026 | A request smuggling vulnerability exists in libsoup's HTTP/1 header parsing logic. The soup_message_headers_append_common() function in libsoup/soup-message-headers.c unconditionally appends each header value without validating for duplicate or conflicting Content-Length fields.… | ||
| CVE-2025-31958 | Low | 0.24 | 3.7 | 0.00 | Apr 21, 2026 | HCL BigFix Service Management is susceptible to HTTP Request Smuggling. HTTP request smuggling vulnerabilities arise when websites route HTTP requests through web servers with inconsistent HTTP parsing. HTTP Smuggling exploits inconsistencies in request parsing between… | ||
| CVE-2026-40175 | Med | 0.24 | 4.8 | 0.02 | Apr 10, 2026 | Axios is a promise based HTTP client for the browser and Node.js. Versions prior to 1.15.0 and 0.3.1 are vulnerable to a specific gadget-style attack chain in which prototype pollution in a third-party dependency may be leveraged to inject unsanitized header values into outbound… | ||
| CVE-2026-34441 | Med | 0.24 | 4.8 | 0.00 | Mar 31, 2026 | cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to version 0.40.0, cpp-httplib is vulnerable to HTTP Request Smuggling. The server's static file handler serves GET responses without consuming the request body. On HTTP/1.1 keep-alive… | ||
| CVE-2021-20220 | Med | 0.24 | 4.8 | 0.01 | Feb 23, 2021 | A flaw was found in Undertow. A regression in the fix for CVE-2020-10687 was found. HTTP request smuggling related to CVE-2017-2666 is possible against HTTP/1.x and HTTP/2 due to permitting invalid characters in an HTTP request. This flaw allows an attacker to poison a… | ||
| CVE-2024-8925 | Low | 0.20 | 3.1 | 0.01 | Oct 8, 2024 | In PHP versions 8.1.* before 8.1.30, 8.2.* before 8.2.24, 8.3.* before 8.3.12, erroneous parsing of multipart form data contained in an HTTP POST request could lead to legitimate data not being processed. This could lead to malicious attacker able to control part of the… | ||
| CVE-2026-53538 | Low | 0.17 | 3.7 | 0.00 | Jun 22, 2026 | Python-Multipart is a streaming multipart parser for Python. Prior to 0.0.30, QuerystringParser treated ; as a field separator in application/x-www-form-urlencoded bodies, in addition to &. The WHATWG URL standard, modern browsers, and Python's urllib.parse (since the… | ||
| CVE-2025-49005 | Low | 0.17 | 3.7 | 0.00 | Jul 3, 2025 | Next.js is a React framework for building full-stack web applications. In Next.js App Router from 15.3.0 to before 15.3.3 and Vercel CLI from 41.4.1 to 42.2.0, a cache poisoning vulnerability was found. The issue allowed page requests for HTML content to return a React Server… | ||
| CVE-2021-41136 | Low | 0.17 | 3.7 | 0.01 | Oct 12, 2021 | Puma is a HTTP 1.1 server for Ruby/Rack applications. Prior to versions 5.5.1 and 4.3.9, using `puma` with a proxy which forwards HTTP header values which contain the LF character could allow HTTP request smugggling. A client could smuggle a request through a proxy, causing the… | ||
| CVE-2026-50052 | Low | 0.15 | — | 0.00 | Jun 3, 2026 | In Vinyl Cache before 9.0.1 and Varnish Cache before 9.0.3, a deficiency in HTTP/2 request parsing can be exploited to launch a backend request desync attack (request smuggling), which in turn can be used for cache poisoning, authentication bypass, or possibly even information… | ||
| CVE-2023-47641 | Low | 0.15 | 3.4 | 0.01 | Nov 14, 2023 | aiohttp is an asynchronous HTTP client/server framework for asyncio and Python. Affected versions of aiohttp have a security vulnerability regarding the inconsistent interpretation of the http protocol. HTTP/1.1 is a persistent protocol, if both Content-Length(CL) and… | ||
| CVE-2021-32715 | Low | 0.13 | 3.1 | 0.01 | Jul 7, 2021 | hyper is an HTTP library for rust. hyper's HTTP/1 server code had a flaw that incorrectly parses and accepts requests with a `Content-Length` header with a prefixed plus sign, when it should have been rejected as illegal. This combined with an upstream HTTP proxy that doesn't… | ||
| CVE-2026-4742 | Low | 0.12 | — | 0.00 | Mar 24, 2026 | Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling') vulnerability in visualfc liteide (liteidex/src/3rdparty/qjsonrpc/src/http-parser modules). This vulnerability is associated with program files http_parser.C. This issue affects liteide: before… | ||
| CVE-2017-12165 | Low | 0.10 | 2.6 | 0.02 | Jul 27, 2018 | It was discovered that Undertow before 1.4.17, 1.3.31 and 2.0.0 processes http request headers with unusual whitespaces which can cause possible http request smuggling. | ||
| CVE-2021-23336 | Med | 0.03 | 5.9 | 0.36 | Feb 15, 2021 | The package python/cpython from 0 and before 3.6.13, from 3.7.0 and before 3.7.10, from 3.8.0 and before 3.8.8, from 3.9.0 and before 3.9.2 are vulnerable to Web Cache Poisoning via urllib.parse.parse_qsl and urllib.parse.parse_qs by using a vector called parameter cloaking.… | ||
| CVE-2005-2088 | 0.02 | — | 0.20 | Jul 5, 2005 | The Apache HTTP server before 1.3.34, and 2.0.x before 2.0.55, when acting as an HTTP proxy, allows remote attackers to poison the web cache, bypass web application firewall protection, and conduct XSS attacks via an HTTP request with both a "Transfer-Encoding: chunked" header… | |||
| CVE-2005-2089 | 0.02 | — | 0.31 | Jul 5, 2005 | Microsoft IIS 5.0 and 6.0 allows remote attackers to poison the web cache, bypass web application firewall protection, and conduct XSS attacks via an HTTP request with both a "Transfer-Encoding: chunked" header and a Content-Length header, which causes IIS to incorrectly handle… | |||
| CVE-2022-29361 | Cri | 0.01 | 9.8 | 0.08 | May 25, 2022 | Improper parsing of HTTP requests in Pallets Werkzeug v2.1.0 and below allows attackers to perform HTTP Request Smuggling using a crafted HTTP request with multiple requests included inside the body. NOTE: the vendor's position is that this behavior can only occur in unsupported… | ||
| CVE-2019-20445 | Cri | 0.01 | 9.1 | 0.13 | Jan 29, 2020 | HttpObjectDecoder.java in Netty before 4.1.44 allows a Content-Length header to be accompanied by a second Content-Length header, or by a Transfer-Encoding header. |
- risk 0.24cvss 3.7epss 0.00
daphne before 4.2.2 reconstructs a raw HTTP request from Twisted's parsed headers and feeds it to autobahn for WebSocket handshake processing. Twisted does not treat \x0b, \x0c, \x1c, \x1d, \x1e, or \x85 as header line separators, but autobahn decodes header values to str and…
- risk 0.24cvss 3.7epss 0.00
A request smuggling vulnerability exists in libsoup's HTTP/1 header parsing logic. The soup_message_headers_append_common() function in libsoup/soup-message-headers.c unconditionally appends each header value without validating for duplicate or conflicting Content-Length fields.…
- risk 0.24cvss 3.7epss 0.00
HCL BigFix Service Management is susceptible to HTTP Request Smuggling. HTTP request smuggling vulnerabilities arise when websites route HTTP requests through web servers with inconsistent HTTP parsing. HTTP Smuggling exploits inconsistencies in request parsing between…
- risk 0.24cvss 4.8epss 0.02
Axios is a promise based HTTP client for the browser and Node.js. Versions prior to 1.15.0 and 0.3.1 are vulnerable to a specific gadget-style attack chain in which prototype pollution in a third-party dependency may be leveraged to inject unsanitized header values into outbound…
- risk 0.24cvss 4.8epss 0.00
cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to version 0.40.0, cpp-httplib is vulnerable to HTTP Request Smuggling. The server's static file handler serves GET responses without consuming the request body. On HTTP/1.1 keep-alive…
- risk 0.24cvss 4.8epss 0.01
A flaw was found in Undertow. A regression in the fix for CVE-2020-10687 was found. HTTP request smuggling related to CVE-2017-2666 is possible against HTTP/1.x and HTTP/2 due to permitting invalid characters in an HTTP request. This flaw allows an attacker to poison a…
- risk 0.20cvss 3.1epss 0.01
In PHP versions 8.1.* before 8.1.30, 8.2.* before 8.2.24, 8.3.* before 8.3.12, erroneous parsing of multipart form data contained in an HTTP POST request could lead to legitimate data not being processed. This could lead to malicious attacker able to control part of the…
- risk 0.17cvss 3.7epss 0.00
Python-Multipart is a streaming multipart parser for Python. Prior to 0.0.30, QuerystringParser treated ; as a field separator in application/x-www-form-urlencoded bodies, in addition to &. The WHATWG URL standard, modern browsers, and Python's urllib.parse (since the…
- risk 0.17cvss 3.7epss 0.00
Next.js is a React framework for building full-stack web applications. In Next.js App Router from 15.3.0 to before 15.3.3 and Vercel CLI from 41.4.1 to 42.2.0, a cache poisoning vulnerability was found. The issue allowed page requests for HTML content to return a React Server…
- risk 0.17cvss 3.7epss 0.01
Puma is a HTTP 1.1 server for Ruby/Rack applications. Prior to versions 5.5.1 and 4.3.9, using `puma` with a proxy which forwards HTTP header values which contain the LF character could allow HTTP request smugggling. A client could smuggle a request through a proxy, causing the…
- risk 0.15cvss —epss 0.00
In Vinyl Cache before 9.0.1 and Varnish Cache before 9.0.3, a deficiency in HTTP/2 request parsing can be exploited to launch a backend request desync attack (request smuggling), which in turn can be used for cache poisoning, authentication bypass, or possibly even information…
- risk 0.15cvss 3.4epss 0.01
aiohttp is an asynchronous HTTP client/server framework for asyncio and Python. Affected versions of aiohttp have a security vulnerability regarding the inconsistent interpretation of the http protocol. HTTP/1.1 is a persistent protocol, if both Content-Length(CL) and…
- risk 0.13cvss 3.1epss 0.01
hyper is an HTTP library for rust. hyper's HTTP/1 server code had a flaw that incorrectly parses and accepts requests with a `Content-Length` header with a prefixed plus sign, when it should have been rejected as illegal. This combined with an upstream HTTP proxy that doesn't…
- risk 0.12cvss —epss 0.00
Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling') vulnerability in visualfc liteide (liteidex/src/3rdparty/qjsonrpc/src/http-parser modules). This vulnerability is associated with program files http_parser.C. This issue affects liteide: before…
- risk 0.10cvss 2.6epss 0.02
It was discovered that Undertow before 1.4.17, 1.3.31 and 2.0.0 processes http request headers with unusual whitespaces which can cause possible http request smuggling.
- risk 0.03cvss 5.9epss 0.36
The package python/cpython from 0 and before 3.6.13, from 3.7.0 and before 3.7.10, from 3.8.0 and before 3.8.8, from 3.9.0 and before 3.9.2 are vulnerable to Web Cache Poisoning via urllib.parse.parse_qsl and urllib.parse.parse_qs by using a vector called parameter cloaking.…
- CVE-2005-2088Jul 5, 2005risk 0.02cvss —epss 0.20
The Apache HTTP server before 1.3.34, and 2.0.x before 2.0.55, when acting as an HTTP proxy, allows remote attackers to poison the web cache, bypass web application firewall protection, and conduct XSS attacks via an HTTP request with both a "Transfer-Encoding: chunked" header…
- CVE-2005-2089Jul 5, 2005risk 0.02cvss —epss 0.31
Microsoft IIS 5.0 and 6.0 allows remote attackers to poison the web cache, bypass web application firewall protection, and conduct XSS attacks via an HTTP request with both a "Transfer-Encoding: chunked" header and a Content-Length header, which causes IIS to incorrectly handle…
- risk 0.01cvss 9.8epss 0.08
Improper parsing of HTTP requests in Pallets Werkzeug v2.1.0 and below allows attackers to perform HTTP Request Smuggling using a crafted HTTP request with multiple requests included inside the body. NOTE: the vendor's position is that this behavior can only occur in unsupported…
- risk 0.01cvss 9.1epss 0.13
HttpObjectDecoder.java in Netty before 4.1.44 allows a Content-Length header to be accompanied by a second Content-Length header, or by a Transfer-Encoding header.