1. Symantec/
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  3. Attack Signatures/
  4. HTTP Hyleos ChemView ActiveX BO

HTTP Hyleos ChemView ActiveX BO

Severity: High

This attack could pose a serious security threat. You should take immediate action to stop any damage or prevent further damage from happening.


This signature detects an attempt for the remote code execution in Hyleos ChemView Activex control.

Additional Information

Hyleos ChemView is a free ActiveX control used to visualize chemical structures from MDL or MOL files.

ChemView is prone to multiple buffer-overflow vulnerabilities because it fails to perform adequate boundary checks on user-supplied data. The vulnerable ActiveX control is 'HyleosChemView.ocx' identified by CLSID:


These issues affect the 'filename' parameter of the 'SaveasMilFile()' and 'ReadMolFile()' methods of HyleoCheView.ocx.

An attacker can exploit these issues by enticing a victim into viewing a malicious webpage. Successful exploits will allow the attacker to execute arbitrary code within the context of the application that uses the ActiveX control (typically Internet Explorer). Failed exploit attempts will result in a denial-of-service condition.

Hyleos ChemView is vulnerable; other versions may also be affected.


  • Hyleos ChemView is vulnerable; other versions may also be affected.

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