Medium: libidn2

Issue Overview:

idn2_to_ascii_4i in lib/lookup.c in GNU libidn2 before 2.1.1 has a heap-based buffer overflow via a long domain string. (CVE-2019-18224)

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.(CVE-2019-12290)

Affected Packages:

libidn2

Issue Correction:
Run yum update libidn2 to update your system.

New Packages:

i686:  
    libidn2-devel-2.3.0-1.4.amzn1.i686  
    libidn2-debuginfo-2.3.0-1.4.amzn1.i686  
    idn2-2.3.0-1.4.amzn1.i686  
    libidn2-2.3.0-1.4.amzn1.i686  
  
src:  
    libidn2-2.3.0-1.4.amzn1.src  
  
x86_64:  
    libidn2-2.3.0-1.4.amzn1.x86_64  
    libidn2-debuginfo-2.3.0-1.4.amzn1.x86_64  
    libidn2-devel-2.3.0-1.4.amzn1.x86_64  
    idn2-2.3.0-1.4.amzn1.x86_64  

Additional References

Red Hat: CVE-2019-12290, CVE-2019-18224

Mitre: CVE-2019-12290, CVE-2019-18224