CVE-2017-6339: Trend Micro InterScan Web Security Virtual Appliance (IWSVA) 6.5 before CP 1746 mismanages certain key and certificate data.

Trend Micro InterScan Web Security Virtual Appliance (IWSVA) 6.5 before CP 1746 mismanages certain key and certificate data.

Trend Micro InterScan Web Security Virtual Appliance (IWSVA) 6.5 before CP 1746 mismanages certain key and certificate data. Per IWSVA documentation, by default, IWSVA acts as a private Certificate Authority (CA) and dynamically generates digital certificates that are sent to client browsers to complete a secure passage for HTTPS connections. It also allows administrators to upload their own certificates signed by a root CA. An attacker with low privileges can download the current CA certificate and Private Key (either the default ones or ones uploaded by administrators) and use those to decrypt HTTPS traffic, thus compromising confidentiality. Also, the default Private Key on this appliance is encrypted with a very weak passphrase. If an appliance uses the default Certificate and Private Key provided by Trend Micro, an attacker can simply download these and decrypt the Private Key using the default/weak passphrase.

Description from the National Vulnerability Database, published by MITRE

What it means for a small business

If your business uses Interscan Web Security Virtual Appliance, install the vendor's update. If you're not sure whether you use it, ask whoever manages your computers.

How likely is an attack? The Exploit Prediction Scoring System, run by FIRST (the global association of security response teams), puts the odds of this one being exploited in the next 30 days at 4.1%, top 9% of all CVEs. That’s above average: worth scheduling this week. Scored October 28, 2026, updated daily.

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Server check: what your web server says about itself, and whether that version has known flaws.

Sources

Part of the Huttenlocher Technologies vulnerability database, refreshed twice a day from CISA and the NVD. The title, category and plain-language guidance are ours; check the linked record before acting on a detail. This is general guidance, not a review of your systems.

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