CVE-2026-55766

A flaw was found in guzzlehttp/psr7, a PHP library for HTTP messages. This vulnerability allows a remote attacker to inject arbitrary header lines into serialized HTTP/1.x messages. The flaw stems from the library's failure to reject carriage return CR and line feed LF characters in HTTP start-li...

CVE-2026-55766

guzzlehttp/psr7 is a PSR-7 HTTP message library implementation in PHP. Prior to 2.12.1, guzzlehttp/psr7 did not reject CR/LF characters in certain first-party HTTP start-line fields: the request method, protocol version, and response reason phrase. If an application placed attacker-controlled dat...

CVE-2026-55766

guzzlehttp/psr7 is a PSR-7 HTTP message library implementation in PHP. Prior to 2.12.1, guzzlehttp/psr7 did not reject CR/LF characters in certain first-party HTTP start-line fields: the request method, protocol version, and response reason phrase. If an application placed attacker-controlled dat...

CVE-2026-55766 guzzlehttp/psr7: CRLF Injection in HTTP Start-Line Serialization

guzzlehttp/psr7 is a PSR-7 HTTP message library implementation in PHP. Prior to 2.12.1, guzzlehttp/psr7 did not reject CR/LF characters in certain first-party HTTP start-line fields: the request method, protocol version, and response reason phrase. If an application placed attacker-controlled dat...

EUVD-2026-38458

guzzlehttp/psr7 is a PSR-7 HTTP message library implementation in PHP. Prior to 2.12.1, guzzlehttp/psr7 did not reject CR/LF characters in certain first-party HTTP start-line fields: the request method, protocol version, and response reason phrase. If an application placed attacker-controlled dat...

CVE-2026-55766

guzzlehttp/psr7 is a PSR-7 HTTP message library implementation in PHP. Prior to 2.12.1, guzzlehttp/psr7 did not reject CR/LF characters in certain first-party HTTP start-line fields: the request method, protocol version, and response reason phrase. If an application placed attacker-controlled dat...

CVE-2026-55766

Summary (CVE-2026-55766): guzzlehttp/psr7 (PHP) before 2.12.1 is vulnerable to CRLF injection in the HTTP start-line fields (method, protocol version, reason phrase) when attacker-controlled data ends up in those fields and the message is serialized or forwarded. The flaw requires the malformed m...

CVE-2026-55766 guzzlehttp/psr7: CRLF Injection in HTTP Start-Line Serialization

guzzlehttp/psr7 is a PSR-7 HTTP message library implementation in PHP. Prior to 2.12.1, guzzlehttp/psr7 did not reject CR/LF characters in certain first-party HTTP start-line fields: the request method, protocol version, and response reason phrase. If an application placed attacker-controlled dat...

CVE-2026-55766 guzzlehttp/psr7: CRLF Injection in HTTP Start-Line Serialization

guzzlehttp/psr7 is a PSR-7 HTTP message library implementation in PHP. Prior to 2.12.1, guzzlehttp/psr7 did not reject CR/LF characters in certain first-party HTTP start-line fields: the request method, protocol version, and response reason phrase. If an application placed attacker-controlled dat...

CVE-2026-55766

guzzlehttp/psr7 is a PSR-7 HTTP message library implementation in PHP. Prior to 2.12.1, guzzlehttp/psr7 did not reject CR/LF characters in certain first-party HTTP start-line fields: the request method, protocol version, and response reason phrase. If an application placed attacker-controlled dat...

JLSEC-2026-616 HTTP/1 client request smuggling via CR/LF in method, target, or host in HTTP.jl

Description The HTTP/1 client serialized request.method and request.target and, in forward-proxy absolute-form, the host verbatim onto the wire with no CR/LF/CTL filtering; the only target validator was wired solely into the server parse path. A caller passing an attacker-influenced URL or method...

CRLF Injection

Overview Affected versions of this package are vulnerable to CRLF Injection in the start-line serialization of the Message class toString, parseRequest, and parseResponse. An attacker can inject header lines and split or smuggle HTTP messages by placing CR or LF characters into the request method...

guzzlehttp/psr7: CRLF Injection in HTTP Start-Line Serialization

Impact guzzlehttp/psr7 did not reject CR/LF characters in certain first-party HTTP start-line fields: the request method, protocol version, and response reason phrase. If an application placed attacker-controlled data into one of those fields and later serialized the PSR-7 message as raw HTTP/1.x...

GHSA-VM85-HXW5-5432 guzzlehttp/psr7: CRLF Injection in HTTP Start-Line Serialization

Impact guzzlehttp/psr7 did not reject CR/LF characters in certain first-party HTTP start-line fields: the request method, protocol version, and response reason phrase. If an application placed attacker-controlled data into one of those fields and later serialized the PSR-7 message as raw HTTP/1.x...

CRLF injection in HTTP start-line serialization

Impact guzzlehttp/psr7 did not reject CR/LF characters in certain first-party HTTP start-line fields: the request method, protocol version, and response reason phrase. If an application placed attacker-controlled data into one of those fields and later serialized the PSR-7 message as raw HTTP/1.x...

CVE-2026-28970

Programs using swift-nio is vulnerable to HTTP request smuggling and HTTP response splitting attacks, caused by insufficient validation of outbound HTTP/1.1 request and response start line components. This vulnerability affects all swift-nio versions from 2.0.0 to 2.99.0. It is fixed in 2.100.0 a...

SwiftNIO: CRLF Injection in outbound HTTP request URI via NIOHTTPRequestHeadersValidator

Programs using swift-nio is vulnerable to HTTP request smuggling and HTTP response splitting attacks, caused by insufficient validation of outbound HTTP/1.1 request and response start line components. This vulnerability affects all swift-nio versions from 2.0.0 to 2.99.0. It is fixed in 2.100.0 a...

GHSA-CQ87-8R7H-962V SwiftNIO: CRLF Injection in outbound HTTP request URI via NIOHTTPRequestHeadersValidator

Programs using swift-nio is vulnerable to HTTP request smuggling and HTTP response splitting attacks, caused by insufficient validation of outbound HTTP/1.1 request and response start line components. This vulnerability affects all swift-nio versions from 2.0.0 to 2.99.0. It is fixed in 2.100.0 a...

PT-2026-48923

Programs using swift-nio is vulnerable to HTTP request smuggling and HTTP response splitting attacks, caused by insufficient validation of outbound HTTP/1.1 request and response start line components. This vulnerability affects all swift-nio versions from 2.0.0 to 2.99.0. It is fixed in 2.100.0 a...

SwiftNIO: CRLF Injection in outbound HTTP request URI via NIOHTTPRequestHeadersValidator

Programs using swift-nio is vulnerable to HTTP request smuggling and HTTP response splitting attacks, caused by insufficient validation of outbound HTTP/1.1 request and response start line components. This vulnerability affects all swift-nio versions from 2.0.0 to 2.99.0. It is fixed in 2.100.0 a...