{"id":"DEBIAN-CVE-2019-12290","details":"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.","modified":"2026-09-09T07:01:09.658189777Z","published":"2019-10-22T16:15:10.877Z","upstream":["CVE-2019-12290"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2019-12290"}],"affected":[{"package":{"name":"libidn2","ecosystem":"Debian:12","purl":"pkg:deb/debian/libidn2?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.2.0-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2019-12290.json"}},{"package":{"name":"libidn2","ecosystem":"Debian:13","purl":"pkg:deb/debian/libidn2?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.2.0-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2019-12290.json"}},{"package":{"name":"libidn2","ecosystem":"Debian:14","purl":"pkg:deb/debian/libidn2?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.2.0-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2019-12290.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N"}]}