Description
UltraVNC revision 1205 has stack-based buffer overflow vulnerability in VNC client code inside ShowConnInfo routine, which leads to a denial of service (DoS) condition. This attack appear to be exploitable via network connectivity. User interaction is required to trigger this vulnerability. This vulnerability has been fixed in revision 1206.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Kaspersky Lab | UltraVNC | 1.2.2.3 | — |
Advisories 5
- ICSA-21-131-11 Siemens SIMATIC UltraVNC HMI WinCC Products CISA ICS & IT advisories · May 6, 2025
- ICSA-21-131-04 Siemens SINAMICS Medium Voltage Products Remote Access (Update B) CISA ICS & IT advisories · May 6, 2025
- SSA-286838 SSA-286838: Multiple Vulnerabilities in SINAMICS Medium Voltage Products Siemens ProductCERT · Aug 10, 2021
- SSA-940818 SSA-940818: UltraVNC Vulnerabilities in SIMATIC HMIs/WinCC Products Siemens ProductCERT · May 11, 2021
- ICSA-20-161-06 Siemens SINUMERIK CISA ICS & IT advisories · Jun 9, 2020
References
- https://ics-cert.kaspersky.com/advisories/klcert-advisories/2019/03/01/klcert-19-009-ultravnc-access-of-memory-location-after-end-of-buffer/
- https://ics-cert.kaspersky.com/advisories/klcert-advisories/2019/03/01/klcert-19-010-ultravnc-stack-based-buffer-overflow/
- https://cert-portal.siemens.com/productcert/pdf/ssa-927095.pdf
- https://www.us-cert.gov/ics/advisories/icsa-20-161-06
- https://cert-portal.siemens.com/productcert/pdf/ssa-940818.pdf
- https://cert-portal.siemens.com/productcert/pdf/ssa-286838.pdf
- https://us-cert.cisa.gov/ics/advisories/icsa-21-131-11