Firefox vulnerability allows reading local data

Firefox vulnerability allows reading local data
About an error in the PDF viewer of Firefox unauthorized can read local files. The vulnerability has since been fixed, updates should be available soon. The error was but already exploited.

In current versions of the Firefox browser with built-in PDF viewer, an error has been discovered which was being exploited by persons unknown. About the weak point can be displayed and upload local files to an external server. Mozilla has already corrected the error. Users are strongly advised to install updates because the bug was already being actively exploited.

Unknown persons spread an exploit the vulnerability via a display on a Russian website. The malicious code reads under Windows from about configuration files for Subversion, and s3browser Filezilla and other FTP clients. On Linux, try the malware to read the password file / etc / passwd, user settings for SSH and historical data for Bash and the databases MySQL and PostgreSQL reported Mozilla security expert Daniel Veditz in a blog entry. Although this special Exploit let Mac users on the sidelines, this version of Firefox is but also vulnerable to the attack. Veditz advises users to replace the passwords and keys. The exploit leave no trace on the compromised computer.

Updates already available

The error was discovered in the implementation of so-called same-origin policy of the JavaScript implementation of the browser. Usually, these safety barrier ensures that only javascript code may be executed whose origin has been validated. In the PDF viewer this manufacturing inspection was obviously not properly implemented. So attackers could not arbitrary Javascript code, but rather execute malicious code in the context of local files and then break out of the sandbox.

Who uses the desktop version of Firefox should update to version 39.0.3 or 38.1.1 ESR. The update will also automatically spread since this morning. The Android version of Firefox does not include a built-in PDF viewer and is therefore not affected by the vulnerability. Perhaps users of Adblockern are also protected from the exploit writes Veditz. What Adblocker software and what appropriate filter should be set, but does not say Veditz.