CVE-2019-12290

Name	CVE-2019-12290
Description	GNU libidn2 before 2.2.0 fails to perform the roundtrip checks specified in RFC3490 Section 4.2 when converting A-labels to U-labels. This makes it possible in some circumstances for one domain to impersonate another. By creating a malicious domain that matches a target domain except for the inclusion of certain punycoded Unicode characters (that would be discarded when converted first to a Unicode label and then back to an ASCII label), arbitrary domains can be impersonated.
Source	CVE (at NVD; CERT, LWN, oss-sec, fulldisc, bugtraq, EDB, Metasploit, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, Mageia, GitHub advisories/code/issues, web search, more)

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
libidn2 (PTS)	buster, buster (security)	2.0.5-1+deb10u1	vulnerable
	bullseye	2.3.0-5	fixed
	bookworm, sid	2.3.3-1	fixed

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

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
libidn2	source	(unstable)	2.2.0-1

Notes

[buster] - libidn2 <no-dsa> (Minor issue; intrusive to backport)
https://gitlab.com/libidn/libidn2/commit/241e8f486134793cb0f4a5b0e5817a97883401f5 (2.2.0)
https://gitlab.com/libidn/libidn2/merge_requests/71