Уязвимость компонента RFC3490 библиотеки Libidn2, позволяющая нарушителю создать вредоносный домен, который соответствует целевому домену

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.