Updated Islamic State's frothing fanatics have leaked online what they claim to be the email addresses and plaintext passwords of 1,500 American military personnel – including CIA staff.

The details include full names, email addresses, unencrypted passwords, ZIP codes, places of work, and telephone numbers. They come in a format that strongly suggests the group got hold of an Excel spreadsheet, converted it into an HTML table, and posted the results on the web.

The self-titled "Islamic State Hacking Divison [sic]" claimed responsibility for the alleged leak on Twitter, and its account was deleted in the past few hours. The data appeared on Tuesday, on a compromised Wordpress-powered website that has languished unused since February this year.

The records include details supposedly on US State Department employees, US Navy, Army and Air Force staff, and NASA bods. There's also a mix of US Embassy staffers, Department of Energy workers, US Postal Service employees, patent office staff, and more.

The "hackers" proclaimed on their webpage "US Military And Government Emails, Passwords, Names, Phone Numbers and Location Information Leaked."

But something's not right. There are lots of entries for people with non-US addresses – such as a worker in an Israeli magistrates' court (court.gov.il), someone in a college in Mississippi (millsaps.edu), a person in the Australian National Audit Office (anao.gov.au), and a UK council worker (stockport.gov.uk).

It's almost as if someone has scraped the public internet for email addresses with "gov" or "mil" in them. There are also just a handful of accounts listed per organization, whereas millions of people work for Uncle Sam.

And the plaintext passwords are hilariously weak – like "david8" weak. The sort of password you wouldn't expect a military or government network to accept. A US Department of Defense source, speaking on condition of anonymity, told The Register the listed passwords are not strong enough to be used on official systems.

We randomly chose and called a number of individuals on the list. In some cases, the numbers worked but no one picked up, and in others, the numbers were disconnected. The dumped information also includes what appears to be three sets of credit card numbers, and screenshots of private Facebook conversations between serving US military personnel discussing operations.

It's unclear where the information came from. It is unclear whether the information is in any way accurate or up to date. It is not clear if the passwords are real or bogus, nor what they can actually be used to access, if anything. It is highly likely the data came from scraping public lists of contact details. There is very little to suggest government systems have been directly compromised.

It's possible the information was acquired by phishing people, who handed over some details about themselves, or by compromising their private social networking accounts, or by obtaining old information leaked from other breached websites.

"As you continue your agression [sic] towards the Islamic State and your bombing campaign against the muslims, know that we are in your emails and computer systems," the Islamic State Hacking Division wackos wrote atop their info dump, "watching and recording your every move, we have your names and addresses, we are in your emails and social media accounts."

A spokeswoman at the Pentagon told The Register officials are aware of the alleged leak. "We cannot confirm credibility at this time. The safety of our service members is always a primary concern," she added. ®

Updated to add

Troy Hunt, who runs the Have I Been Pwned website, has weighed in, pointing out many flaws in the dumped data: the listed folks "are often not in defence or intelligence roles," and "the data is almost certainly from multiple locations and very unlikely to be from a single data breach."

Crucially, as El Reg suspected, "most of the data is easily discoverable via either existing data breaches or information intentionally made public," Hunt noted.