CVE-2019-12290 Information

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.

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Reference

http://lists.opensuse.org/opensuse-security-announce/2019-12/msg00008.html http://lists.opensuse.org/opensuse-security-announce/2019-12/msg00009.html https://gitlab.com/libidn/libidn2/commit/241e8f486134793cb0f4a5b0e5817a97883401f5 https://gitlab.com/libidn/libidn2/commit/614117ef6e4c60e1950d742e3edf0a0ef8d389de https://gitlab.com/libidn/libidn2/merge_requests/71 https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/3UFT76Y7OSGPZV3EBEHD6ISVUM3DLARM/ https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/KXDKYWFV6N2HHVSE67FFDM7G3FEL2ZNE/ https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/ONG3GJRRJO35COPGVJXXSZLU4J5Y42AT/ https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/RSI4TI2JTQWQ3YEUX5X36GTVGKO4QKZ5/ https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/U6ZXL2RDNQRAHCMKWPOMJFKYJ344X4HL/ https://security.gentoo.org/glsa/202003-63 https://usn.ubuntu.com/4168-1/

Attack Complexity

LOW

Privileges Required

NONE

User Interaction Required

NONE

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

NONE

Availability Impact

HIGH

Base Score

NONE

Base Severity

7.5