EIP-0e1ca3ec

A vulnerability exists within UltraVNC’s “vncviewer.exe” client. A malicious server can trigger an arbitrary memory write condition through a flaw in the function ClientConnection::SolidColor while drawing pixel data to the screen. An attacker can leverage this in conjunction with other vulnerabilities to execute code in the context of the UltraVNC Viewer process.

Vulnerability Identifiers

• Exodus Intelligence: EIP-0e1ca3ec
• MITRE CVE: PENDING

Vulnerability Metrics

• CVSSv2 Score: 5.8

Vendor References

• https://uvnc.com/downloads/ultravnc/146-ultravnc-1-3-6-0.html

Discovery Credit

• Exodus Intelligence

Disclosure Timeline

• Disclosed to affected vendor: December 8th, 2021
• Disclosed to public: December 16th, 2021

Further Information

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