CVE-2019-16785

Name	CVE-2019-16785
Description	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 server does not parse header fields with an LF the same way as it does those with a CRLF it can lead to the front-end and the back-end server parsing the same HTTP message in two different ways. This can lead to a potential for HTTP request smuggling/splitting whereby Waitress may see two requests while the front-end server only sees a single HTTP message. This issue is fixed in Waitress 1.4.0.
Source	CVE (at NVD; CERT, LWN, oss-sec, fulldisc, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)
References	DLA-3000-1
Debian Bugs	947306

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
waitress (PTS)	jessie, jessie (lts)	0.8.9-2+deb8u1	vulnerable
	stretch (security), stretch (lts), stretch	1.0.1-1+deb9u1	fixed
	buster (security), buster, buster (lts)	1.2.0~b2-2+deb10u1	fixed
	bullseye (security), bullseye	1.4.4-1.1+deb11u1	fixed
	bookworm	2.1.2-2	fixed
	sid, trixie	3.0.1-1	fixed

The information below is based on the following data on fixed versions.

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
waitress	source	wheezy	(unfixed)	end-of-life
waitress	source	stretch	1.0.1-1+deb9u1		DLA-3000-1
waitress	source	buster	1.2.0~b2-2+deb10u1
waitress	source	(unstable)	1.4.1-1			947306

Notes

[jessie] - waitress <no-dsa> (Minor issue)
https://github.com/Pylons/waitress/security/advisories/GHSA-pg36-wpm5-g57p
https://github.com/Pylons/waitress/commit/8eba394ad75deaf9e5cd15b78a3d16b12e6b0eba