CVE-2026-44546

Name	CVE-2026-44546
Description	daphne before 4.2.2 reconstructs a raw HTTP request from Twisted's parsed headers and feeds it to autobahn for WebSocket handshake processing. Twisted does not treat \x0b, \x0c, \x1c, \x1d, \x1e, or \x85 as header line separators, but autobahn decodes header values to str and calls splitlines(). An attacker can exploit this parser differential to inject additional headers into the ASGI scope passed to the application. daphne now rejects requests with these bytes in any header value with a 400 response.
Source	CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)
Debian Bugs	1138864

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
python-daphne (PTS)	bullseye	3.0.1-1	vulnerable
	bookworm	4.0.0-1	vulnerable
	trixie	4.1.2-2	vulnerable
	forky, sid	4.2.1-2	vulnerable

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

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
python-daphne	source	(unstable)	(unfixed)			1138864

Notes

[trixie] - python-daphne <no-dsa> (Minor issue)
[bookworm] - python-daphne <no-dsa> (Minor issue)
[bullseye] - python-daphne <postponed> (Minor issue)
Fixed by: https://github.com/django/daphne/commit/2628b7b2e6a196afff58defee3d77671a28de631 (4.2.2)