CVE-2019-12290

published 2019-10-22

CVE-2019-12290: 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…

Priority P3 42 high 7.5 CVSS 3.1

AV N AC L PR N UI N S U C N I H A N

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.

Affected

7 ranges

Vendor	Product	Version range	Fixed in
debian	libidn2	< libidn2 2.2.0-1 (bookworm)	libidn2 2.2.0-1 (bookworm)
gnu	libidn2	< 2.2.0	2.2.0
gnu	libidn2	>= 0 < 2.2.0-1	2.2.0-1
gnu	libidn2	>= 0 < 2.2.0-1	2.2.0-1
gnu	libidn2	>= 0 < 2.2.0-1	2.2.0-1
gnu	libidn2	>= 0 < 2.2.0-1	2.2.0-1
gnu	libidn2	>= 0 < 2.0.4-1.1ubuntu0.2	2.0.4-1.1ubuntu0.2

CVSS provenance

nvd v3.1 7.5 HIGH CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

nvd v2.0 5.0 MEDIUM AV:N/AC:L/Au:N/C:N/I:P/A:N

osv 7.5 HIGH

vendor_debian 7.5 HIGH

vendor_ubuntu 7.5 HIGH

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CWE-20