Describe CVE-2018-18557.
What is CVE-2018-18557?
LibTIFF 3.9.3, 3.9.4, 3.9.5, 3.9.6, 3.9.7, 4.0.0alpha4, 4.0.0alpha5, 4.0.0alpha6, 4.0.0beta7, 4.0.0, 4.0.1, 4.0.2, 4.0.3, 4.0.4, 4.0.4beta, 4.0.5, 4.0.6, 4.0.7, 4.0.8 and 4.0.9 (with JBIG enabled) decodes arbitrarily-sized JBIG into a buffer, ignoring the buffer size, which leads to a tif_jbig.c JBIGDecode out-of-bounds write..