EIP-5182fb5b

A vulnerability exists within UltraVNC view due to a lack of proper stack memory buffer cleanup before constructing the ‘rfbTextChat’ message, which results in a leak of 3-bytes of stack memory. 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-5182fb5b
• MITRE CVE: 

Vulnerability Metrics

• CVSSv2 Score: 4.3

Vendor References

• https://github.com/ultravnc/UltraVNC/releases/tag/1.3.4

Discovery Credit

• Exodus Intelligence

Disclosure Timeline

• Disclosed to affected vendor: June 21th, 2021
• Disclosed to public: September 25th, 2021

Further Information

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