UltraVNC revision 1211 has a heap buffer overflow vulnerability in VNC server code inside file transfer request handler, which can potentially result in code execution. This attack appears to be exploitable via network connectivity. This vulnerability has been fixed in revision 1212.
Source: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2019-8273
Reference (s):
- https://cert-portal.siemens.com/productcert/pdf/ssa-927095.pdf
- https://ics-cert.kaspersky.com/advisories/klcert-advisories/2019/03/01/klcert-19-020-ultravnc-heap-based-buffer-overflow/
- https://www.us-cert.gov/ics/advisories/icsa-20-161-06