MiKTeX 2.9.6840 has been released on September 30, 2018.

Release notes

Fixed security issues

CVE-2018-17407

This applies to MiKTeX (TeX Live is an upstream source):

An issue was discovered in t1_check_unusual_charstring functions in writet1.c files in TeX Live before 2018-09-21. A buffer overflow in the handling of Type 1 fonts allows arbitrary code execution when a malicious font is loaded by one of the vulnerable tools: pdflatex, pdftex, dvips, or luatex.

More info: https://nvd.nist.gov/vuln/detail/CVE-2018-17407

Fixed issues

  • 199: miktex searches the whole file system if grffile is used