Vulnerability Note VU#190939

HP Online Support Services ActiveX AppendStringToFile() arbitrary file writing

Original Release date: 06 Jun 2008 | Last revised: 07 Jun 2008


The HP Online Support Services ActiveX control contains a method called AppendStringToFile(). This may allow a remote, unauthenticated attacker to write to files on a vulnerable system.


HP Services provides online product support services including HP Instant Support. The HPISDataManager.dll ActiveX control contains the insecure function AppendStringToFile(), which can be exploited by a malicious attacker to execute arbitrary files on a vulnerable system.

Note that the HP Support Services ActiveX control is locked to certain domains, such as This means that an attacker would have to subvert the host name lookup methodology on a victim's system or exploit a cross-site scripting vulnerability in one of the allowed domains to exploit this vulnerability.


A remote, unauthenticated attacker could exploit this vulnerability to write to arbitrary files on a vulnerable system.


HP suggests to install HP Instant Support - v1.0.0.24 or later. For installation instructions, please visit the HP Support Document. However, limited testing has shown that this update does not change the behavior with respect to unsafe methods.

From the HP Support Document:

    The vulnerabilities can also be resolved by the following procedure:

    Set the kill bit for the vulnerable ActiveX control's Class identifier (CLSID) {14C1B87C-3342-445F-9B5E-365FF330A3AC} . The kill bit is set by modifying the data value of the Compatibility Flags DWORD value for the CLSID of this ActiveX control to 0x00000400. This is explained in Microsoft's article KB240797 or subsequent.

Systems Affected (Learn More)

VendorStatusDate NotifiedDate Updated
Hewlett-Packard CompanyAffected11 Apr 200807 Jun 2008
If you are a vendor and your product is affected, let us know.

CVSS Metrics (Learn More)

Group Score Vector
Base N/A N/A
Temporal N/A N/A
Environmental N/A N/A



Hewlett-Packard credits Dennis Rand of CSIS Security Research and Intelligence for discovering this vulnerability.

This document was written by Joseph Pruszynski and Will Dormann.

Other Information


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