CVE 2018-14883
An issue was discovered in PHP before 5.6.37, 7.0.x before 7.0.31, 7.1.x before 7.1.20, and 7.2.x before 7.2.8. An Integer Overflow leads to a heap-based buffer over-read in exif_thumbnail_
See the 
CVE page on Mitre.org
for more details.
