Relaxed Flash: Blitzableiter Checks for Malicious Flash Files
On stimulus from the German Federal Agency for Information Security (BSI), Felix "FX" Lindner of the Phenoelit hacker group investigated the security of Flash object code. The result is a free protection program with the name Blitzableiter ("lightning rod").
Lindner checked into the security model for Adobe's Rich Application Platform and found out that the interpreted Flash object code leaves open many security holes that could lead to problems for users and hosts having Flash content. He discovered that the Flash Player has indeed two virtual machines. The more commonly used older Adobe Virtual Machine (AVM1) actually provides attackers the greatest opportunity because of its multitude of supported, backwards-compatible version formats. The second VM, AVM2, Adobe released as open source under the codename Tamarin, but not too many content providers are currently using it. At least according to Lindner's public presentation at the 26th Congress of the Chaos Computer Club in Berlin.
Lindner, who is a regular attendee at the Chaos congresses, found this two-VM solution a problem in that it leads to complex code that in special cases may lead to errors in the Flash compiler. To protect Flash users from such problems, Lindner, under the Blitzableiter project name, wrote a kind of recompiler that analyzes existing SWF files for embedded ActionScript code and cleans them up, to prevent problem cases with possible vulnerabilities from occurring. The tool may double the code size, but could detect all problem cases in the test set. It let through over 80% of the problem-free code. Because 20% were false positives, Lindner sees room for improvement and set up a subproject for reporting such cases, apologizing for his "limited developer qualifications." Nonetheless, he's offering the software for download under GPLv3.
Subscribe to our Linux Newsletters
Find Linux and Open Source Jobs
Subscribe to our ADMIN Newsletters
Support Our Work
Linux Magazine content is made possible with support from readers like you. Please consider contributing when you’ve found an article to be beneficial.
News
-
Gnome 47.1 Released with a Few Fixes
The latest release of the Gnome desktop is all about fixing a few nagging issues and not about bringing new features into the mix.
-
System76 Unveils an Ampere-Powered Thelio Desktop
If you're looking for a new desktop system for developing autonomous driving and software-defined vehicle solutions. System76 has you covered.
-
VirtualBox 7.1.4 Includes Initial Support for Linux kernel 6.12
The latest version of VirtualBox has arrived and it not only adds initial support for kernel 6.12 but another feature that will make using the virtual machine tool much easier.
-
New Slimbook EVO with Raw AMD Ryzen Power
If you're looking for serious power in a 14" ultrabook that is powered by Linux, Slimbook has just the thing for you.
-
The Gnome Foundation Struggling to Stay Afloat
The foundation behind the Gnome desktop environment is having to go through some serious belt-tightening due to continued financial problems.
-
Thousands of Linux Servers Infected with Stealth Malware Since 2021
Perfctl is capable of remaining undetected, which makes it dangerous and hard to mitigate.
-
Halcyon Creates Anti-Ransomware Protection for Linux
As more Linux systems are targeted by ransomware, Halcyon is stepping up its protection.
-
Valve and Arch Linux Announce Collaboration
Valve and Arch have come together for two projects that will have a serious impact on the Linux distribution.
-
Hacker Successfully Runs Linux on a CPU from the Early ‘70s
From the office of "Look what I can do," Dmitry Grinberg was able to get Linux running on a processor that was created in 1971.
-
OSI and LPI Form Strategic Alliance
With a goal of strengthening Linux and open source communities, this new alliance aims to nurture the growth of more highly skilled professionals.