In PHP before 5.6.31, 7.x before 7.0.21, and 7.1.x before 7.1.7, an error in the date extension's timelib_meridian parsing code could be used by attackers able to supply date strings to leak information from the interpreter, related to ext/date/lib/parse_date.c out-of-bounds reads affecting the php_parse_date function. NOTE: the correct fix is in the e8b7698f5ee757ce2c8bd10a192a491a498f891c commit, not the bd77ac90d3bdf31ce2a5251ad92e9e75 gist.