Diary reader Wayne Smith shared an interesting malicious document with us. Wayne also provided us with his own analysis: this malicious document sleeps and checks the time online before it activates its payload.

First we take a look at the sample (md5 7EAB96D2BC04CA155DE035815B88EE00) with oledump.py.

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Its a VBS file, let" />

Analysis of this obfuscated code reveals that it is a downloader with a particular property (for a maldoc): before downloading and executing the payload, this VBS code will sleep for 5 minutes, checking the elapsed time every minute by querying http://time.nist.gov:13.

By sleeping and checking the time online, this sample hopes to evade detection by sandboxes that do time acceleration without interfering with online time checking. This sample will sleep indefinitely when online time querying fails.

Didier Stevens
Microsoft MVP Consumer Security
blog.DidierStevens.com DidierStevensLabs.com

(c) SANS Internet Storm Center. https://isc.sans.edu Creative Commons Attribution-Noncommercial 3.0 United States License.

Enlarge (credit: Christiaan Colen)

Filippo Valsorda is an engineer on the Cloudflare Cryptography team, where he's deploying and helping design TLS 1.3, the next revision of the protocol implementing HTTPS. He also created a Heartbleed testing site in 2014. This post originally appeared on his blog and is re-printed with his permission.

After years of wrestling with GnuPG with varying levels of enthusiasm, I came to the conclusion that it's just not worth it, and I'm giving up—at least on the concept of long-term PGP keys. This editorial is not about the gpg tool itself, or about tools at all. Many others have already written about that. It's about the long-term PGP key model—be it secured by Web of Trust, fingerprints or Trust on First Use—and how it failed me.

Trust me when I say that I tried. I went through all the setups. I used Enigmail. I had offline master keys on a dedicated Raspberry Pi with short-lived subkeys. I wrote custom tools to make handwritten paper backups of offline keys (which I'll publish sooner or later). I had YubiKeys. Multiple. I spent days designing my public PGP policy.

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