Feeds

IE bug leaks private details from 50m PDF files

Black hat recon courtesy of Microsoft

Beginner's guide to SSL certificates

A bug in Microsoft's Internet Explorer browser is causing more than 50 million files stored online to leak potentially sensitive information that could compromise user privacy, a security researcher said.

The documents stored in Adobe's PDF format display the internal disk location where the file is stored, an oversight that can inadvertently expose real-world names and login IDs of users, the operating system being used and other information that is better kept private. The data can then be retrieved using simple web searches.

Google searches such as this one expose almost four million documents residing on users' C drives alone. Combined with searches for other common drives, the technique exposes more than 50 million files that display the local disk path, according to Inferno, a security researcher for a large software company who asked that his real name not be used.

"If they have those kind of PDFs, somebody can use search engines to find out user names or do more reconnaissance on the operating systems used," he told The Register. "That actually invades the privacy of a user."

The potentially sensitive data is included in PDFs that have been printed using Internet Explorer. The full path location is appended to its contents as soon as the Microsoft browser is used to print the document. Although the data isn't always exposed when the document is viewed with Adobe Reader, it is easily readable when the file is opened in editors such as Notepad, and the text is also available to Google and other search engines.

This PDF, for example, was stored at C:\Program Files\Wids7\WizardReport.htm at time of printing. The path makes it clear that the file was stored on a Windows machine that has software from Worldwide Instructional Design System installed. Other PDFs give up directory names that reveal authors, projects or other data that may have been designated confidential.

The only way to remove the path is erase the text in an editor and save the document.

All versions of IE suffer from the bug. A Microsoft spokeswoman said company engineers are working to reproduce the reported behavior. "We can confirm that this is not a vulnerability," she wrote in an email.

Adobe representatives didn't reply to requests for comment. Inferno's report is here. ®

Protecting users from Firesheep and other Sidejacking attacks with SSL

More from The Register

next story
Spies would need SUPER POWERS to tap undersea cables
Why mess with armoured 10kV cables when land-based, and legal, snoop tools are easier?
Early result from Scots indyref vote? NAW, Jimmy - it's a SCAM
Anyone claiming to know before tomorrow is telling porkies
Apple Pay is a tidy payday for Apple with 0.15% cut, sources say
Cupertino slurps 15 cents from every $100 purchase
Israeli spies rebel over mass-snooping on innocent Palestinians
'Disciplinary treatment will be sharp and clear' vow spy-chiefs
YouTube, Amazon and Yahoo! caught in malvertising mess
Cisco says 'Kyle and Stan' attack is spreading through compromised ad networks
Hackers pop Brazil newspaper to root home routers
Step One: try default passwords. Step Two: Repeat Step One until success
China hacked US Army transport orgs TWENTY TIMES in ONE YEAR
FBI et al knew of nine hacks - but didn't tell TRANSCOM
Microsoft to patch ASP.NET mess even if you don't
We know what's good for you, because we made the mess says Redmond
NORKS ban Wi-Fi and satellite internet at embassies
Crackdown on tardy diplomatic sysadmins providing accidental unfiltered internet access
prev story

Whitepapers

Providing a secure and efficient Helpdesk
A single remote control platform for user support is be key to providing an efficient helpdesk. Retain full control over the way in which screen and keystroke data is transmitted.
WIN a very cool portable ZX Spectrum
Win a one-off portable Spectrum built by legendary hardware hacker Ben Heck
Saudi Petroleum chooses Tegile storage solution
A storage solution that addresses company growth and performance for business-critical applications of caseware archive and search along with other key operational systems.
Protecting users from Firesheep and other Sidejacking attacks with SSL
Discussing the vulnerabilities inherent in Wi-Fi networks, and how using TLS/SSL for your entire site will assure security.
Security for virtualized datacentres
Legacy security solutions are inefficient due to the architectural differences between physical and virtual environments.