Description
UltraVNC revision 1198 contains multiple memory leaks (CWE-655) in VNC client code, which allow an attacker to read stack memory and can be abused for information disclosure. Combined with another vulnerability, it can be used to leak stack memory and bypass ASLR. This attack appears to be exploitable via network connectivity. These vulnerabilities have been fixed in revision 1199.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| UltraVNC | 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-19-005-ultravnc-memory-leak/
- 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