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.
A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc().
The product writes data past the end, or before the beginning, of the intended buffer.
| Link | Tags |
|---|---|
| https://ics-cert.kaspersky.com/advisories/klcert-advisories/2019/03/01/klcert-19-020-ultravnc-heap-based-buffer-overflow/ | third party advisory |
| https://cert-portal.siemens.com/productcert/pdf/ssa-927095.pdf | third party advisory |
| https://www.us-cert.gov/ics/advisories/icsa-20-161-06 | third party advisory us government resource |