Symantec is phasing in a new trust mark to ensure Web users that the sites they are visiting are safe. Symantec has been replacing "VeriSign Trusted" with "Norton Secured, powered by VeriSign."

When Kaspersky Lab last week spotted code-signed Trojan malware dubbed Mediyes that had been signed with a digital certificate owned by Swiss firm Conpavi AG and issued by Symantec, it touched off a hunt to determine the source of the problem.

Security firm Kaspersky Lab Thursday said it's identified a malicious program that appears to make use of a compromised Symantec VeriSign digital certificate issued to Conpavi AG, which is known to work with Swiss government agencies. Kaspersky says it has asked Symantec VeriSign to revoke the compromised certificates.

Security companies have recently identified multiple malware threats that use stolen digital certificates to sign their components in an attempt to avoid detection and bypass Windows defenses.

Qualys, the Redwood Shores, Calif.-based security firm specializing in vulnerability assessment and management, is poised for an initial public offering (IPO) later this year.