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CWE-444

402 CVEs • Abstraction: Base

Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')

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.

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CVEs (402)

CVE
VENDORS
PRODUCTS
UPDATED
PUBLISHED
CVSS
1Ibm
1Websphere Application Server
Aug 5, 2026
Jul 28, 2026
N/A· v4
8.7 HIGH· v3
N/A· v2
IBM WebSphere Application Server 9.0, and 8.5 and IBM WebSphere Application Server - Liberty 17.0.0.3 through 26.0.0.7 is vulnerable to HTTP Response Smuggling due to improper handling of non-standard HTTP version tokens...Show more
IBM WebSphere Application Server 9.0, and 8.5 and IBM WebSphere Application Server - Liberty 17.0.0.3 through 26.0.0.7 is vulnerable to HTTP Response Smuggling due to improper handling of non-standard HTTP version tokens.Show less
-
-
Jul 30, 2026
Jul 28, 2026
6.9 MEDIUM· v4
7.5 HIGH· v3
N/A· v2
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...Show more
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 validation. Attackers can craft a header value containing a complete additional HTTP request that is interpreted as a separate request by backends such as Go net/http and Python http.server, causing the backend to process a smuggled request with attacker-chosen method, path, and headers that bypasses the rouille handler's access control logic.Show less
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-
Jul 30, 2026
Jul 28, 2026
6.3 MEDIUM· v4
5.4 MEDIUM· v3
N/A· v2
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...Show more
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 upstream backends unchanged while transmitting a body already de-chunked by tiny_http, enabling CL.TE desynchronization attacks where attackers control where the backend believes the request body ends.Show less
-
-
Jul 30, 2026
Jul 28, 2026
6.3 MEDIUM· v4
5.4 MEDIUM· v3
N/A· v2
tiny-http through 0.12.0 contains an HTTP request smuggling vulnerability that allows remote attackers to desynchronize request framing by sending a Transfer-Encoding header with any value, including non-chunked codings,...Show more
tiny-http through 0.12.0 contains an HTTP request smuggling vulnerability that allows remote attackers to desynchronize request framing by sending a Transfer-Encoding header with any value, including non-chunked codings, which causes the library to unconditionally apply chunk-decoding and discard Content-Length. Attackers can exploit the discrepancy between tiny_http's improper Transfer-Encoding parsing and a correctly-implemented front-end proxy to produce two distinct interpretations of a single byte stream, enabling request smuggling, and can additionally send non-chunked bodies with non-chunked Transfer-Encoding values to cause failed body reads that tie up connections and consume worker threads without signaling errors to clients.Show less
2Gnome
Redhat
2Enterprise Linux
Libsoup
Aug 24, 2026
Jul 24, 2026
N/A· v4
7.2 HIGH· v3
N/A· v2
A flaw was found in libsoup. The chunked transfer encoding parser uses a permissive parsing function for chunk sizes that silently accepts inputs violating RFC 9112, including leading whitespace, plus sign prefixes, and...Show more
A flaw was found in libsoup. The chunked transfer encoding parser uses a permissive parsing function for chunk sizes that silently accepts inputs violating RFC 9112, including leading whitespace, plus sign prefixes, and trailing invalid characters. When libsoup operates behind a strict frontend proxy, this parsing differential can be exploited to smuggle HTTP requests.Show less
1Apple
1Swiftnio Http/2
Sep 1, 2026
Jul 23, 2026
N/A· v4
5.3 MEDIUM· v3
N/A· v2
SwiftNIO HTTP/2 was missing validation on inbound HEADERS frames that let CR, LF, NUL, SP and other control characters reach an HTTP/1.1 backend through NIOHTTP2's HTTP/2-to-HTTP/1 codec, enabling HTTP request smuggling...Show more
SwiftNIO HTTP/2 was missing validation on inbound HEADERS frames that let CR, LF, NUL, SP and other control characters reach an HTTP/1.1 backend through NIOHTTP2's HTTP/2-to-HTTP/1 codec, enabling HTTP request smuggling or response splitting. This vulnerability is addressed in swift-nio-http2 version 1.45.0.Show less
-
-
Jul 20, 2026
Jul 17, 2026
7.8 HIGH· v4
N/A· v3
N/A· v2
Skipper is an HTTP router and reverse proxy for service composition. Prior to 0.26.10, zalando/skipper's OpenPolicyAgent integration silently bypasses request-body inspection on HTTP/1.1 Transfer-Encoding: chunked and HT...Show more
Skipper is an HTTP router and reverse proxy for service composition. Prior to 0.26.10, zalando/skipper's OpenPolicyAgent integration silently bypasses request-body inspection on HTTP/1.1 Transfer-Encoding: chunked and HTTP/2 requests that omit the content-length pseudo-header, because the opaAuthorizeRequestWithBody filter and OpenPolicyAgentInstance.ExtractHttpBodyOptionally in filters/openpolicyagent/openpolicyagent.go produce an empty raw_body and input.parsed_body while the upstream service receives the full attacker-controlled body. This issue is fixed in version 0.26.10.Show less
-
-
Jul 16, 2026
Jul 16, 2026
6.3 MEDIUM· v4
N/A· v3
N/A· v2
Inconsistent interpretation of HTTP requests (HTTP response smuggling) vulnerability in elixir-mint mint allows a malicious HTTP/1 server to desynchronize a strict intermediary and the Mint client on the same pooled conn...Show more
Inconsistent interpretation of HTTP requests (HTTP response smuggling) vulnerability in elixir-mint mint allows a malicious HTTP/1 server to desynchronize a strict intermediary and the Mint client on the same pooled connection, enabling response-queue poisoning against subsequent requests that share the connection. The Mint.HTTP1.decode_body/5 function in lib/mint/http1.ex parses the chunk-size line of a Transfer-Encoding: chunked response with Integer.parse(data, 16). RFC 7230 defines chunk-size = 1*HEXDIG and forbids any sign prefix, but Integer.parse/2 accepts an optional leading + or -. A chunk-size line of +5 is accepted as a five-byte chunk; lines of +0 and -0 are accepted as the terminating zero-length chunk and end the message body early. An RFC-strict intermediary in the response path rejects these forms, so the intermediary and the Mint client disagree on where one response ends and the next begins. On a pooled keep-alive connection, an attacker-influenced origin can inject bytes that the client attributes to the next legitimate response on the same connection, poisoning the response queue and corrupting the responses returned to unrelated in-flight requests. This issue affects mint: from 0.1.0 before 1.9.3.Show less
1Eclipse
1Grizzly
Jul 27, 2026
Jul 14, 2026
6.3 MEDIUM· v4
5.3 MEDIUM· v3
N/A· v2
Eclipse Grizzly in versions before 5.0.2, cannot properly parse the trailer section in malformed trailer header's line, which can be leveraged to perform HTTP request smuggling. Grizzly 5.0.1 supports system properties t...Show more
Eclipse Grizzly in versions before 5.0.2, cannot properly parse the trailer section in malformed trailer header's line, which can be leveraged to perform HTTP request smuggling. Grizzly 5.0.1 supports system properties that enable the behavior that fixes the vulnerability - set org.glassfish.grizzly.http.STRICT_HEADER_NAME_VALIDATION_RFC_9110 and org.glassfish.grizzly.http.STRICT_HEADER_VALUE_VALIDATION_RFC_9110 system properties to "true".Show less
-
-
Jul 14, 2026
Jul 14, 2026
N/A· v4
9.1 CRITICAL· v3
N/A· v2
Due to an HTTP Request Smuggling vulnerability in SAP Approuter, an unauthenticated attacker could send a specially crafted HTTP request that leads to request-response desynchronization. This could result in the exposure...Show more
Due to an HTTP Request Smuggling vulnerability in SAP Approuter, an unauthenticated attacker could send a specially crafted HTTP request that leads to request-response desynchronization. This could result in the exposure of user responses and cause the system to become unavailable. This leads to a high impact on confidentiality and availability.Show less
1Openvpn
1Openvpn Access Server
Jul 10, 2026
Jul 8, 2026
6.9 MEDIUM· v4
7.5 HIGH· v3
N/A· v2
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
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-
Jul 14, 2026
Jul 2, 2026
N/A· v4
N/A· v3
N/A· v2
Rejected reason: DO NOT USE THIS CVE RECORD. ConsultIDs: none. Reason: This record was withdrawn by its CNA. Further investigation showed that it was not a security issue. Notes: none.
1Ibm
1Websphere Application Server
Jul 29, 2026
Jun 30, 2026
N/A· v4
9.8 CRITICAL· v3
N/A· v2
IBM CICS Transaction Gateway for Multiplatforms 9.1, 9.2, 9.3, and 10.1 IBM WebSphere Application Server 9.0, and 8.5 and IBM WebSphere Application Server - Liberty 17.0.0.3 through 26.0.0.6 are affected by an HTTP reque...Show more
IBM CICS Transaction Gateway for Multiplatforms 9.1, 9.2, 9.3, and 10.1 IBM WebSphere Application Server 9.0, and 8.5 and IBM WebSphere Application Server - Liberty 17.0.0.3 through 26.0.0.6 are affected by an HTTP request smuggling vulnerability.Show less
1Ibm
1Websphere Application Server
Jul 2, 2026
Jun 30, 2026
N/A· v4
7.5 HIGH· v3
N/A· v2
IBM WebSphere Application Server - Liberty 17.0.0.3 through 26.0.0.6 is affected by an arbitrary file read vulnerability with the restConnector-2.0 feature enabled.
1Amazon
1Application Load Balancer
Jul 1, 2026
Jun 29, 2026
7.9 HIGH· v4
9.8 CRITICAL· v3
N/A· v2
Inconsistent interpretation of HTTP/2 requests in AWS Application Load Balancer with AWS WAF enabled might allow remote actors to bypass AWS WAF managed rule body inspection via crafted HTTP/2 requests that fragment the...Show more
Inconsistent interpretation of HTTP/2 requests in AWS Application Load Balancer with AWS WAF enabled might allow remote actors to bypass AWS WAF managed rule body inspection via crafted HTTP/2 requests that fragment the request body across frames so that only a partial body is inspected. This issue only impacts HTTP/2 ALB target groups. To remediate this issue, customers should enable the "Inspect after sufficient data" target group configuration associated to an ALB load balancer. Refer to: ( https://docs.aws.amazon.com/elasticloadbalancing/latest/application/edit-target-group-attributes.html#waf-http2-inspection )Show less
1Amazon
1Cloudfront
Jul 1, 2026
Jun 29, 2026
7.9 HIGH· v4
9.8 CRITICAL· v3
N/A· v2
Inconsistent interpretation of HTTP/2 requests in Amazon CloudFront with AWS WAF enabled might allow remote actors to bypass AWS WAF managed rule body inspection via crafted HTTP/2 requests that fragment the request body...Show more
Inconsistent interpretation of HTTP/2 requests in Amazon CloudFront with AWS WAF enabled might allow remote actors to bypass AWS WAF managed rule body inspection via crafted HTTP/2 requests that fragment the request body across frames so that only a partial body is inspected. This issue was remediated server-side. No customer action is required.Show less
1Nghttp2
1Nghttp2
Jun 30, 2026
Jun 28, 2026
6.3 MEDIUM· v4
5.4 MEDIUM· v3
N/A· v2
nghttp2's nghttpx proxy through 1.69.0 forwards an HTTP/1.1 Upgrade request that also carries a Content-Length header and body onto reusable keep-alive backend connections, re-adding the Upgrade and Connection headers wh...Show more
nghttp2's nghttpx proxy through 1.69.0 forwards an HTTP/1.1 Upgrade request that also carries a Content-Length header and body onto reusable keep-alive backend connections, re-adding the Upgrade and Connection headers while passing Content-Length verbatim. A backend that resolves the resulting ambiguous message in the attacker's favor enables HTTP request/response smuggling and cross-client response-queue poisoning.Show less
1Envoyproxy
1Envoy
Jun 29, 2026
Jun 26, 2026
N/A· v4
7.5 HIGH· v3
N/A· v2
Envoy is an open source edge and service proxy designed for cloud-native applications. Prior to 1.35.11, 1.36.7, 1.37.3, and 1.38.1, Envoy can translate a downstream HTTP/3 request that is complete at the transport layer...Show more
Envoy is an open source edge and service proxy designed for cloud-native applications. Prior to 1.35.11, 1.36.7, 1.37.3, and 1.38.1, Envoy can translate a downstream HTTP/3 request that is complete at the transport layer (HEADERS with FIN / headers-only close) but still carries a nonzero Content-Length into a complete upstream HTTP/1 request with unresolved body debt. In an HTTP/1 upstream deployment where the origin replies before reading the declared body and keeps the connection reusable, the beginning of the next Envoy-generated upstream request can be consumed as the first request's body. The remaining bytes are then parsed by the origin as a new HTTP/1 request. This was reproduced as a route-bypass/desync: direct /pwn was denied by Envoy, but the second downstream H3 stream received the response for backend-parsed GET /pwn HTTP/1.1. This vulnerability is fixed in 1.35.11, 1.36.7, 1.37.3, and 1.38.1.Show less
1Caddyserver
1Caddy
Jul 15, 2026
Jun 23, 2026
N/A· v4
8.1 HIGH· v3
N/A· v2
Caddy is an extensible server platform that uses TLS by default. Prior to 2.11.4, forward_auth copy_headers deletes the exact client-supplied identity header before copying the trusted value from the auth gateway. But wh...Show more
Caddy is an extensible server platform that uses TLS by default. Prior to 2.11.4, forward_auth copy_headers deletes the exact client-supplied identity header before copying the trusted value from the auth gateway. But when the request later goes through php_fastcgi, Caddy normalizes HTTP headers into CGI variables by replacing - with _. This lets a client send an underscore alias that survives the forward_auth delete step but becomes the same PHP/FastCGI variable. Result: a remote client can inject or sometimes override identity/group headers trusted by PHP/FastCGI applications behind Caddy. This vulnerability is fixed in 2.11.4.Show less
1Vllm
1Vllm
Sep 1, 2026
Jun 22, 2026
N/A· v4
9.1 CRITICAL· v3
N/A· v2
vLLM is an inference and serving engine for large language models (LLMs). From 0.3.0 until 0.22.0, a vulnerability in ASGI web servers and starlette's trust on those web servers enables an authentication bypass of the Op...Show more
vLLM is an inference and serving engine for large language models (LLMs). From 0.3.0 until 0.22.0, a vulnerability in ASGI web servers and starlette's trust on those web servers enables an authentication bypass of the OpenAI API AuthenticationMiddleware. It allows to use the API without providing the configured VLLM_API_KEY or --api-key. This vulnerability is fixed in 0.22.0.Show less