libevent: libevent: Multiple HTTP Parser Bugs Enable Request Smuggling

A flaw was found in libevent. The evhttp parser in libevent's http.c component inconsistently handles HTTP Transfer-Encoding headers and chunked framing. This inconsistency allows an unauthenticated remote attacker to desynchronize request boundaries when libevent is used behind a proxy. Successf...

libevent: libevent: Multiple HTTP Parser Bugs Enable Request Smuggling

A flaw was found in libevent. The evhttp parser in libevent's http.c component inconsistently handles HTTP Transfer-Encoding headers and chunked framing. This inconsistency allows an unauthenticated remote attacker to desynchronize request boundaries when libevent is used behind a proxy. Successf...

libevent: Libevent: HTTP header handling bugs create risk of access control bypass.

A flaw was found in libevent. The evhttpdecodeuriinternal function in http.c decodes percent-encoded %00 bytes into literal NUL characters without rejecting them, allowing an attacker to craft a URI such as /admin/secret%00.jpg where extension-based access checks see .jpg but the server processes...

UBUNTU-CVE-2023-54397

Tornado before 6.3.3 contains an HTTP request smuggling vulnerability...

CVE-2023-54397

Tornado before 6.3.3 contains an HTTP request smuggling vulnerability...

CVE-2024-40725

Herramienta de Detección de HTTP Request Smuggling Este repositorio contiene una herramienta basada en Python para detectar vulnerabilidades de HTTP Request Smuggling, dirigida específicamente a CVE-2024-40725. La herramienta intenta explotar esta vulnerabilidad en el servidor HTTP Apache enviand...

CVE-2026-69217

Http4s is a Scala interface for HTTP services. Prior to 0.23.35 and 1.0.0-M47, Ember’s HTTP/1.1 parser accepts differing duplicate Content-Length headers and uses the last value instead of rejecting the message. When an Ember server is behind a keep-alive intermediary that selects a different...

CVE-2026-69205

Http4s is a Scala interface for HTTP services. Prior to 0.23.35 and 1.0.0-M47, Ember’s HeaderP.parse uses a case-sensitive substring test for the Transfer-Encoding value and decodes header bytes with the platform default charset. Values such as Chunked are not recognized, values such as notchunke...

Http4s: Ember chunk parser lenience (TE.TE request smuggling)

Summary Ember's chunk decoder parses the size token leniently: it strips leading and trailing whitespace and accepts a leading + or - sign. RFC9112 §7.1 defines chunk-size = 1HEXDIG. An intermediary that parses the chunk boundary differently or rejects it will disagree with Ember on request...

CVE-2026-69217 Http4s: Ember Server accepts duplicate Content-Length headers

Http4s is a Scala interface for HTTP services. Prior to 0.23.35 and 1.0.0-M47, Ember’s HTTP/1.1 parser accepts differing duplicate Content-Length headers and uses the last value instead of rejecting the message. When an Ember server is behind a keep-alive intermediary that selects a different...

CVE-2026-69217

Http4s (a Scala HTTP service interface) is vulnerable to CL.CL request smuggling due to its Ember HTTP/1.1 parser accepting differing duplicate Content-Length headers and using the last value instead of rejecting the message. Affected versions are prior to 0.23.35 and 1.0.0-M47 . When an Ember se...

EUVD-2026-79193

Http4s is a Scala interface for HTTP services. Prior to 0.23.35 and 1.0.0-M47, Ember’s HTTP/1.1 parser accepts differing duplicate Content-Length headers and uses the last value instead of rejecting the message. When an Ember server is behind a keep-alive intermediary that selects a different...

CVE-2026-69217 Http4s: Ember Server accepts duplicate Content-Length headers

Http4s is a Scala interface for HTTP services. Prior to 0.23.35 and 1.0.0-M47, Ember’s HTTP/1.1 parser accepts differing duplicate Content-Length headers and uses the last value instead of rejecting the message. When an Ember server is behind a keep-alive intermediary that selects a different...

CVE-2026-69216

Http4s is a Scala interface for HTTP services. Prior to 0.23.35 and 1.0.0-M47, Ember’s chunk decoder trims the chunk-size token and accepts leading plus or minus signs instead of requiring one or more hexadecimal digits followed by the required CRLF. When an intermediary forwards chunked data...

CVE-2026-69204

Http4s is a Scala interface for HTTP services. Prior to 0.23.35 and 1.0.0-M47, Ember HTTP/1.1 does not reject messages containing both Transfer-Encoding and Content-Length, so an intermediary and Ember can select different body framing rules. When ember-server is behind a keep-alive intermediary...

EUVD-2026-79190

Http4s is a Scala interface for HTTP services. Prior to 0.23.35 and 1.0.0-M47, Ember’s HeaderP.parse uses a case-sensitive substring test for the Transfer-Encoding value and decodes header bytes with the platform default charset. Values such as Chunked are not recognized, values such as notchunke...

CVE-2026-69205 Http4s: Ember Transfer-Encoding value parsing (TE.CL / TE.0 request smuggling)

Http4s is a Scala interface for HTTP services. Prior to 0.23.35 and 1.0.0-M47, Ember’s HeaderP.parse uses a case-sensitive substring test for the Transfer-Encoding value and decodes header bytes with the platform default charset. Values such as Chunked are not recognized, values such as notchunke...

CVE-2026-69205 Http4s: Ember Transfer-Encoding value parsing (TE.CL / TE.0 request smuggling)

Http4s is a Scala interface for HTTP services. Prior to 0.23.35 and 1.0.0-M47, Ember’s HeaderP.parse uses a case-sensitive substring test for the Transfer-Encoding value and decodes header bytes with the platform default charset. Values such as Chunked are not recognized, values such as notchunke...

CVE-2026-69205 Http4s: Ember Transfer-Encoding value parsing (TE.CL / TE.0 request smuggling)

Http4s is a Scala interface for HTTP services. Prior to 0.23.35 and 1.0.0-M47, Ember’s HeaderP.parse uses a case-sensitive substring test for the Transfer-Encoding value and decodes header bytes with the platform default charset. Values such as Chunked are not recognized, values such as notchunke...

CVE-2026-69205

Http4s (a Scala HTTP library) is affected in its Ember backend, specifically the HeaderP.parse function, which uses a case-sensitive substring test for the Transfer-Encoding value and decodes header bytes with the platform default charset. This causes mismatches with RFC-compliant intermediaries,...