503228 - Unhandled error from BrowserFeedWriter close() method reveals installation path

Status: RESOLVED FIXED

(Firefox :: General, defect)

Description

[Gregory Fleischer]

User-Agent:       Mozilla/5.0 (X11; U; Linux i686 (x86_64); en-US; rv:1.9.0.11) Gecko/2009060214 Firefox/3.0.11
Build Identifier: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.1pre) Gecko/20090708 Shiretoko/3.5.1pre

Calling the close() method on a newly created BrowserFeedWriter instance generates a detailed error message that includes the file location of FeedWriter.js.

For users that install Firefox on their desktop or other non-standard location, this behavior may reduce their privacy.  

Reproducible: Always

Comment 1

[Gregory Fleischer]

Attachment: example of reading detailed error message

Example of how exception from BrowserFeedWriter close() method can be used to determine installation path.

Comment 2

[Johnathan Nightingale [:johnath]]

cc'ng Mano for evaluation.  Gregory - these bugs with detailed test cases are really helpful, thank you.

Comment 3

[:Gavin Sharp [email: [e-mail]]]

This is a specific case of bug 267645; there are potentially many of these. See also bug 268370.

Comment 4

[Jesse Ruderman]

Gregory disclosed this bug today during his DEFCON presentation, "Attacking Tor at the Application Layer".

Comment 5

[Marco Castelluccio [:marco]]

I think this bug is solved, because the Gregory's test output is:
'found location: "resource:///components/FeedWriter.js"'

Comment 6

[Tom Ritter [:tjr]]

We removed the particular API in question.