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 15 of 20| CVE | Vendor / Product | Sev | Risk | CVSS | EPSS | KEV | Published | Description |
|---|---|---|---|---|---|---|---|---|
| CVE-2023-34037 | Med | 0.34 | 5.3 | 0.00 | Aug 4, 2023 | VMware Horizon Server contains a HTTP request smuggling vulnerability. A malicious actor with network access may be able to perform HTTP smuggle requests. | ||
| CVE-2025-4366 | Med | 0.33 | 6.1 | 0.00 | May 22, 2025 | A request smuggling vulnerability identified within Pingora’s proxying framework, pingora-proxy, allows malicious HTTP requests to be injected via manipulated request bodies on cache HITs, leading to unauthorized request execution and potential cache poisoning. Fixed in: … | ||
| CVE-2021-33037 | Med | 0.33 | 5.3 | 0.75 | Jul 12, 2021 | Apache Tomcat 10.0.0-M1 to 10.0.6, 9.0.0.M1 to 9.0.46 and 8.5.0 to 8.5.66 did not correctly parse the HTTP transfer-encoding request header in some circumstances leading to the possibility to request smuggling when used with a reverse proxy. Specifically: - Tomcat incorrectly… | ||
| CVE-2021-21295 | Med | 0.33 | 5.9 | 0.19 | Mar 9, 2021 | Netty is an open-source, asynchronous event-driven network application framework for rapid development of maintainable high performance protocol servers & clients. In Netty (io.netty:netty-codec-http2) before version 4.1.60.Final there is a vulnerability that enables request… | ||
| CVE-2020-7658 | Med | 0.33 | 6.1 | 0.01 | May 22, 2020 | meinheld prior to 1.0.2 is vulnerable to HTTP Request Smuggling. HTTP pipelining issues and request smuggling attacks might be possible due to incorrect Content-Length and Transfer encoding header parsing. | ||
| CVE-2020-7655 | Med | 0.33 | 6.1 | 0.01 | May 21, 2020 | netius prior to 1.17.58 is vulnerable to HTTP Request Smuggling. HTTP pipelining issues and request smuggling attacks might be possible due to incorrect Transfer encoding header parsing which could allow for CL:TE or TE:TE attacks. | ||
| CVE-2026-6338 | Med | 0.32 | — | 0.00 | Jun 11, 2026 | A HTTP request smuggling and desynchronization vulnerability affects Kong Gateway Enterprise 3.4, 3.10, 3.11, 3.12, 3.13, and 3.14 series. The vulnerability is caused by a parsing flaw in Kong’s HTTP request processing pipeline when handling untrusted HTTP/1.1 traffic. | ||
| CVE-2021-21409 | Med | 0.32 | 5.9 | 0.05 | Mar 30, 2021 | Netty is an open-source, asynchronous event-driven network application framework for rapid development of maintainable high performance protocol servers & clients. In Netty (io.netty:netty-codec-http2) before version 4.1.61.Final there is a vulnerability that enables request… | ||
| CVE-2020-1935 | Med | 0.32 | 4.8 | 0.09 | Feb 24, 2020 | In Apache Tomcat 9.0.0.M1 to 9.0.30, 8.5.0 to 8.5.50 and 7.0.0 to 7.0.99 the HTTP header parsing code used an approach to end-of-line parsing that allowed some invalid HTTP headers to be parsed as valid. This led to a possibility of HTTP Request Smuggling if Tomcat was located… | ||
| CVE-2019-17569 | Med | 0.32 | 4.8 | 0.09 | Feb 24, 2020 | The refactoring present in Apache Tomcat 9.0.28 to 9.0.30, 8.5.48 to 8.5.50 and 7.0.98 to 7.0.99 introduced a regression. The result of the regression was that invalid Transfer-Encoding headers were incorrectly processed leading to a possibility of HTTP Request Smuggling if… | ||
| CVE-2026-62899 | Med | 0.31 | 5.9 | 0.01 | Aug 11, 2026 | Inconsistent interpretation of http requests ('http request/response smuggling') in .NET allows an unauthorized attacker to bypass a security feature over a network. | ||
| CVE-2026-6324 | Med | 0.31 | 4.8 | 0.01 | May 29, 2026 | A flaw was found in libsoup. A remote attacker could exploit an unsigned to signed conversion error in the `soup_body_input_stream_read_chunked()` function by sending a malicious HTTP request. This vulnerability occurs when libsoup operates behind a non-libsoup proxy server or… | ||
| CVE-2026-42581 | Med | 0.31 | 5.8 | 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, HttpObjectDecoder strips a conflicting Content-Length header when a request carries both Transfer-Encoding: chunked and Content-Length, but only for HTTP/1.1 messages.… | ||
| CVE-2025-66373 | Med | 0.31 | 4.8 | 0.00 | Dec 4, 2025 | Akamai Ghost on Akamai CDN edge servers before 2025-11-17 has a chunked request body processing error that can result in HTTP request smuggling. When Akamai Ghost receives an invalid chunked body that includes a chunk size different from the actual size of the following chunk… | ||
| CVE-2025-6442 | Med | 0.31 | 5.9 | 0.00 | Jun 25, 2025 | Ruby WEBrick read_header HTTP Request Smuggling Vulnerability. This vulnerability allows remote attackers to smuggle arbitrary HTTP requests on affected installations of Ruby WEBrick. This issue is exploitable when the product is deployed behind an HTTP proxy that fulfills… | ||
| CVE-2022-39163 | Med | 0.31 | 4.7 | 0.00 | Mar 26, 2025 | IBM Cognos Controller 11.0.0 through 11.1.0 is vulnerable to a Client-Side Desync (CSD) attack where an attacker could exploit a desynchronized browser connection that could lead to further cross-site scripting (XSS) attacks. | ||
| CVE-2024-9666 | Med | 0.31 | 4.7 | 0.00 | Nov 25, 2024 | A vulnerability was found in the Keycloak Server. The Keycloak Server is vulnerable to a denial of service (DoS) attack due to improper handling of proxy headers. When Keycloak is configured to accept incoming proxy headers, it may accept non-IP values, such as obfuscated… | ||
| CVE-2024-23326 | Med | 0.31 | 5.9 | 0.00 | Jun 4, 2024 | Envoy is a cloud-native, open source edge and service proxy. A theoretical request smuggling vulnerability exists through Envoy if a server can be tricked into adding an upgrade header into a response. Per RFC https://www.rfc-editor.org/rfc/rfc7230#section-6.7 a server sends 101… | ||
| CVE-2024-21647 | Med | 0.31 | 5.9 | 0.01 | Jan 8, 2024 | Puma is a web server for Ruby/Rack applications built for parallelism. Prior to version 6.4.2, puma exhibited incorrect behavior when parsing chunked transfer encoding bodies in a way that allowed HTTP request smuggling. Fixed versions limits the size of chunk extensions.… | ||
| CVE-2023-38697 | Med | 0.31 | 5.8 | 0.01 | Aug 4, 2023 | protocol-http1 provides a low-level implementation of the HTTP/1 protocol. RFC 9112 Section 7.1 defined the format of chunk size, chunk data and chunk extension. The value of Content-Length header should be a string of 0-9 digits, the chunk size should be a string of hex digits… |
- risk 0.34cvss 5.3epss 0.00
VMware Horizon Server contains a HTTP request smuggling vulnerability. A malicious actor with network access may be able to perform HTTP smuggle requests.
- risk 0.33cvss 6.1epss 0.00
A request smuggling vulnerability identified within Pingora’s proxying framework, pingora-proxy, allows malicious HTTP requests to be injected via manipulated request bodies on cache HITs, leading to unauthorized request execution and potential cache poisoning. Fixed in: …
- risk 0.33cvss 5.3epss 0.75
Apache Tomcat 10.0.0-M1 to 10.0.6, 9.0.0.M1 to 9.0.46 and 8.5.0 to 8.5.66 did not correctly parse the HTTP transfer-encoding request header in some circumstances leading to the possibility to request smuggling when used with a reverse proxy. Specifically: - Tomcat incorrectly…
- risk 0.33cvss 5.9epss 0.19
Netty is an open-source, asynchronous event-driven network application framework for rapid development of maintainable high performance protocol servers & clients. In Netty (io.netty:netty-codec-http2) before version 4.1.60.Final there is a vulnerability that enables request…
- risk 0.33cvss 6.1epss 0.01
meinheld prior to 1.0.2 is vulnerable to HTTP Request Smuggling. HTTP pipelining issues and request smuggling attacks might be possible due to incorrect Content-Length and Transfer encoding header parsing.
- risk 0.33cvss 6.1epss 0.01
netius prior to 1.17.58 is vulnerable to HTTP Request Smuggling. HTTP pipelining issues and request smuggling attacks might be possible due to incorrect Transfer encoding header parsing which could allow for CL:TE or TE:TE attacks.
- risk 0.32cvss —epss 0.00
A HTTP request smuggling and desynchronization vulnerability affects Kong Gateway Enterprise 3.4, 3.10, 3.11, 3.12, 3.13, and 3.14 series. The vulnerability is caused by a parsing flaw in Kong’s HTTP request processing pipeline when handling untrusted HTTP/1.1 traffic.
- risk 0.32cvss 5.9epss 0.05
Netty is an open-source, asynchronous event-driven network application framework for rapid development of maintainable high performance protocol servers & clients. In Netty (io.netty:netty-codec-http2) before version 4.1.61.Final there is a vulnerability that enables request…
- risk 0.32cvss 4.8epss 0.09
In Apache Tomcat 9.0.0.M1 to 9.0.30, 8.5.0 to 8.5.50 and 7.0.0 to 7.0.99 the HTTP header parsing code used an approach to end-of-line parsing that allowed some invalid HTTP headers to be parsed as valid. This led to a possibility of HTTP Request Smuggling if Tomcat was located…
- risk 0.32cvss 4.8epss 0.09
The refactoring present in Apache Tomcat 9.0.28 to 9.0.30, 8.5.48 to 8.5.50 and 7.0.98 to 7.0.99 introduced a regression. The result of the regression was that invalid Transfer-Encoding headers were incorrectly processed leading to a possibility of HTTP Request Smuggling if…
- risk 0.31cvss 5.9epss 0.01
Inconsistent interpretation of http requests ('http request/response smuggling') in .NET allows an unauthorized attacker to bypass a security feature over a network.
- risk 0.31cvss 4.8epss 0.01
A flaw was found in libsoup. A remote attacker could exploit an unsigned to signed conversion error in the `soup_body_input_stream_read_chunked()` function by sending a malicious HTTP request. This vulnerability occurs when libsoup operates behind a non-libsoup proxy server or…
- risk 0.31cvss 5.8epss 0.01
Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final and 4.1.133.Final, HttpObjectDecoder strips a conflicting Content-Length header when a request carries both Transfer-Encoding: chunked and Content-Length, but only for HTTP/1.1 messages.…
- risk 0.31cvss 4.8epss 0.00
Akamai Ghost on Akamai CDN edge servers before 2025-11-17 has a chunked request body processing error that can result in HTTP request smuggling. When Akamai Ghost receives an invalid chunked body that includes a chunk size different from the actual size of the following chunk…
- risk 0.31cvss 5.9epss 0.00
Ruby WEBrick read_header HTTP Request Smuggling Vulnerability. This vulnerability allows remote attackers to smuggle arbitrary HTTP requests on affected installations of Ruby WEBrick. This issue is exploitable when the product is deployed behind an HTTP proxy that fulfills…
- risk 0.31cvss 4.7epss 0.00
IBM Cognos Controller 11.0.0 through 11.1.0 is vulnerable to a Client-Side Desync (CSD) attack where an attacker could exploit a desynchronized browser connection that could lead to further cross-site scripting (XSS) attacks.
- risk 0.31cvss 4.7epss 0.00
A vulnerability was found in the Keycloak Server. The Keycloak Server is vulnerable to a denial of service (DoS) attack due to improper handling of proxy headers. When Keycloak is configured to accept incoming proxy headers, it may accept non-IP values, such as obfuscated…
- risk 0.31cvss 5.9epss 0.00
Envoy is a cloud-native, open source edge and service proxy. A theoretical request smuggling vulnerability exists through Envoy if a server can be tricked into adding an upgrade header into a response. Per RFC https://www.rfc-editor.org/rfc/rfc7230#section-6.7 a server sends 101…
- risk 0.31cvss 5.9epss 0.01
Puma is a web server for Ruby/Rack applications built for parallelism. Prior to version 6.4.2, puma exhibited incorrect behavior when parsing chunked transfer encoding bodies in a way that allowed HTTP request smuggling. Fixed versions limits the size of chunk extensions.…
- risk 0.31cvss 5.8epss 0.01
protocol-http1 provides a low-level implementation of the HTTP/1 protocol. RFC 9112 Section 7.1 defined the format of chunk size, chunk data and chunk extension. The value of Content-Length header should be a string of 0-9 digits, the chunk size should be a string of hex digits…