Libidn - (bulletinoct2019)ID: oval:org.secpod.oval:def:2105274 | Date: (C)2020-01-19 (M)2023-11-13 |
Class: PATCH | Family: unix |
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.