Design/Logic Flaw

Waitress through version 1.3.1 implemented a "MAY" part of the RFC7230 which states: "Although the line terminator for the start-line and header fields is the sequence CRLF, a recipient MAY recognize a single LF as a line terminator and ignore any preceding CR." Unfortunately if a front-end serve...

CVE-2019-16786

Waitress through version 1.3.1 would parse the Transfer-Encoding header and only look for a single string value, if that value was not chunked it would fall through and use the Content-Length header instead. According to the HTTP standard Transfer-Encoding should be a comma separated list, with t...

PYSEC-2019-136

Waitress through version 1.3.1 implemented a "MAY" part of the RFC7230 which states: "Although the line terminator for the start-line and header fields is the sequence CRLF, a recipient MAY recognize a single LF as a line terminator and ignore any preceding CR." Unfortunately if a front-end serve...

Design/Logic Flaw

Waitress through version 1.3.1 would parse the Transfer-Encoding header and only look for a single string value, if that value was not chunked it would fall through and use the Content-Length header instead. According to the HTTP standard Transfer-Encoding should be a comma separated list, with t...

PYSEC-2019-136

Waitress through version 1.3.1 implemented a "MAY" part of the RFC7230 which states: "Although the line terminator for the start-line and header fields is the sequence CRLF, a recipient MAY recognize a single LF as a line terminator and ignore any preceding CR." Unfortunately if a front-end serve...

PYSEC-2019-137

Waitress through version 1.3.1 would parse the Transfer-Encoding header and only look for a single string value, if that value was not chunked it would fall through and use the Content-Length header instead. According to the HTTP standard Transfer-Encoding should be a comma separated list, with t...

UBUNTU-CVE-2019-16785

Waitress through version 1.3.1 implemented a "MAY" part of the RFC7230 which states: "Although the line terminator for the start-line and header fields is the sequence CRLF, a recipient MAY recognize a single LF as a line terminator and ignore any preceding CR." Unfortunately if a front-end serve...

UBUNTU-CVE-2019-16786

Waitress through version 1.3.1 would parse the Transfer-Encoding header and only look for a single string value, if that value was not chunked it would fall through and use the Content-Length header instead. According to the HTTP standard Transfer-Encoding should be a comma separated list, with t...

PYSEC-2019-66

Waitress through version 1.3.1 implemented a "MAY" part of the RFC7230 which states: "Although the line terminator for the start-line and header fields is the sequence CRLF, a recipient MAY recognize a single LF as a line terminator and ignore any preceding CR." Unfortunately if a front-end serve...

HTTP Request Smuggling: Content-Length Sent Twice in Waitress

Impact Waitress would header fold a double Content-Length header and due to being unable to cast the now comma separated value to an integer would set the Content-Length to 0 internally. So a request with: Content-Length: 10 Content-Length: 10 would get transformed to: Content-Length: 10, 10 Whic...

GHSA-4PPP-GPCR-7QF6 HTTP Request Smuggling: Content-Length Sent Twice in Waitress

Impact Waitress would header fold a double Content-Length header and due to being unable to cast the now comma separated value to an integer would set the Content-Length to 0 internally. So a request with: Content-Length: 10 Content-Length: 10 would get transformed to: Content-Length: 10, 10 Whic...

HTTP Request Smuggling: Invalid Transfer-Encoding in Waitress

Impact Waitress would parse the Transfer-Encoding header and only look for a single string value, if that value was not chunked it would fall through and use the Content-Length header instead. According to the HTTP standard Transfer-Encoding should be a comma separated list, with the inner-most...

GHSA-G2XC-35JW-C63P HTTP Request Smuggling: Invalid Transfer-Encoding in Waitress

Impact Waitress would parse the Transfer-Encoding header and only look for a single string value, if that value was not chunked it would fall through and use the Content-Length header instead. According to the HTTP standard Transfer-Encoding should be a comma separated list, with the inner-most...

HTTP Request Smuggling: LF vs CRLF handling in Waitress

Impact Waitress implemented a "MAY" part of the RFC7230 https://tools.ietf.org/html/rfc7230section-3.5 which states: Although the line terminator for the start-line and header fields is the sequence CRLF, a recipient MAY recognize a single LF as a line terminator and ignore any preceding CR...

GHSA-PG36-WPM5-G57P HTTP Request Smuggling: LF vs CRLF handling in Waitress

Impact Waitress implemented a "MAY" part of the RFC7230 https://tools.ietf.org/html/rfc7230section-3.5 which states: Although the line terminator for the start-line and header fields is the sequence CRLF, a recipient MAY recognize a single LF as a line terminator and ignore any preceding CR...

CVE-2019-16785

Waitress through version 1.3.1 implemented a "MAY" part of the RFC7230 which states: "Although the line terminator for the start-line and header fields is the sequence CRLF, a recipient MAY recognize a single LF as a line terminator and ignore any preceding CR." Unfortunately if a front-end serve...

CVE-2019-16785

Summary: The vulnerability CVE-2019-16785 affects Waitress (Python WSGI server) up to v1.3.1. It relates to RFC7230’s line-termination rule: Waitress may treat messages inconsistently when a proxy uses LF vs CRLF, enabling HTTP request smuggling/splitting. Impact is the front-end and back-end par...

CVE-2019-16785

Waitress through version 1.3.1 implemented a "MAY" part of the RFC7230 which states: "Although the line terminator for the start-line and header fields is the sequence CRLF, a recipient MAY recognize a single LF as a line terminator and ignore any preceding CR." Unfortunately if a front-end serve...

CVE-2019-16785 HTTP Request Smuggling: LF vs CRLF handling in Waitress

Waitress through version 1.3.1 implemented a "MAY" part of the RFC7230 which states: "Although the line terminator for the start-line and header fields is the sequence CRLF, a recipient MAY recognize a single LF as a line terminator and ignore any preceding CR." Unfortunately if a front-end serve...

CVE-2019-16786 HTTP Request Smuggling: Invalid Transfer-Encoding in Waitress

Waitress through version 1.3.1 would parse the Transfer-Encoding header and only look for a single string value, if that value was not chunked it would fall through and use the Content-Length header instead. According to the HTTP standard Transfer-Encoding should be a comma separated list, with t...