Friday, August 1, 2014

jsunpack online

jsunpack is now online in a temporary capacity. the disk performance is worse than previous places jsunpack has been hosted so please let me know if its bearable. picture of the hosting environment below:

Thursday, March 20, 2014

Jsunpack offline (for now) is offline today for expected downtime.
I hope to bring the server online soon, but I unfortunately don't know how soon.

More details if you email me at urule99 {on the} gmail 


Monday, June 3, 2013

Jsunpack server migration in progress

Hey everybody, I'm upgrading the jsunpack server again. I'm hoping there will be no downtime during this period. Thanks.

[Edit] All done! I love it when everything goes smoothly.

Monday, April 22, 2013

Update to Jsunpack PDF parsing

Hey guys, I just added a patch from David Dorsey of Visiblerisk, Inc. (Thanks David, you are a boss!).

Below is a sample PDF you can test with just to see how awesome it is:

David described a lot of the improvements and the analysis he performed at the following blog posts entitled "Analyzing Malicious PDFs or: How I Learned to Stop Worrying and Love Adobe Reader"
Part 1:
Part 2:

In brief, this update improves's XFA parsing, PDF encryption tags, and generally the update will help you to decode some malicious PDFs where had trouble decoding them before.

Thanks to David and please if you see any bugs related to this update please report them at and I'll fix them.


Monday, October 3, 2011

New jsunpack server!

I brought a new server online for over the weekend and everything should be operating normally now. I expect this server to last about 6 months based on the volume of past submissions. I hope you enjoy it!


Wednesday, June 15, 2011

The jsunpack website is accepting submissions again

I removed the ability for people to submit URLs and files to, partially due to abusive submissions in late May. I brought the submissions interface back online today with some changes to help prevent further abuse. Please let me know if you encounter any sort of problems.

Friday, April 1, 2011

Temporary downtime for jsunpack website

The website for this project has been down for the past 2 days because I was moving it to new hardware. The old hardware was running ESXi and caused all virtual machines to lock up repeatedly. While I was moving it the site was completely offline but I'm happy to say its back now!

Keep in mind, if you had been running jsunpack-n locally then you wouldn't have experienced any problems (thats software is freely available and that is what the server is running).

[off topic] I've seen a few people do a great job in downtime situations, none of which I did because this whole project is running from a single virtual machine with limited resources. For instance, when Netflix was recently down they acknowledged the problem and credited subscriber's accounts. When another site was down, they played a funny "Doh!" error message video from the Simpsons. In yet another case, DreamHost apologized and wrote a funny blog about it (note: I do not use or endorse DreamHost but I do read their blog). Some quotes from that post:

"I’d like compensation. You’ve earned it! You pay for 365 days of service – not 364.375"

"Why didn’t you call me? We would have loved to reach out to every customer individually, but with over one million domains hosted, that could – quite literally – have taken all year. We’d have loved to email you too, but well, we had this little network problem blocking emails."