exiv2: An infinite loop and hang (CVE-2019-20421)

In Jp2Image::readMetadata() in jp2image.cpp in Exiv2 0.27.2, an input file can result in an infinite loop and hang, with high CPU consumption. Remote attackers could leverage this vulnerability to cause a denial of service via a crafted file.

References:

• https://github.com/Exiv2/exiv2/issues/1011
• https://nvd.nist.gov/vuln/detail/CVE-2019-20421

Patch:

https://github.com/Exiv2/exiv2/commit/a82098f4f90cd86297131b5663c3dec6a34470e8