New SSL Attack Lets a Malicious Listener Steal Session Cookies
New flaw in an old encryption scheme leaves the experts scrambling to disable SSL 3
Researchers at Google have discovered a flaw in SSL 3 that allows "the plaintext of secure connections to be calculated by a network attacker." The vulnerability, known as POODLE (Padding Oracle On Downgraded Legacy Extension), is a form of man-in-the-middle attack, in which the attacker injects malicious JavaScript into the victim's browser. The attack, which is especially dangerous for an insecure wireless network such as a coffee house or other public space, results in information disclosure. For instance, the attacker can obtain session cookies from the target browser and use them to access the victim's online accounts.
SSL 3 is over 18 years old, and has long since been deprecated in favor of more advanced technologies, such as the heir-apparent TLS protocol, which is now the recommended replacement for SSL. The real problem is that browsers and servers are often configured to negotiate an encryption protocol. If the highest level protocol isn't available, the server will allow a connection with a less secure alternative. The attacker can thus coax the target to use SSL 3 even if more secure options are available.
The POODLE problem is not something that is easily patched, and, given the fact that SSL 3 is obsolete anyway, experts are advising users,admins, and developers to disable it. Mozilla has announced that SSL 3 will be disabled by default in the Firefox 34 release, which is due in November.
According to the post at the Google Online Security blog, "...our recommended response is to support TLS_FALLBACK_SCSV. This is a mechanism that solves the problems caused by retrying failed connections and thus prevents attackers from inducing browsers to use SSL 3.0. It also prevents downgrades from TLS 1.2 to 1.1 or 1.0 and so may help prevent future attacks." The TLS_FALLBACK_SCSV indicator was created by Google and implemented for Chrome browsers. Mozilla has announced that it will implement TLS_FALLBACK_SCSV in Firefox in early 2015.
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
-
Juno Computers Launches Another Linux Laptop
If you're looking for a powerhouse laptop that runs Ubuntu, the Juno Computers Neptune 17 v6 should be on your radar.
-
ZorinOS 17.1 Released, Includes Improved Windows App Support
If you need or desire to run Windows applications on Linux, there's one distribution intent on making that easier for you and its new release further improves that feature.
-
Linux Market Share Surpasses 4% for the First Time
Look out Windows and macOS, Linux is on the rise and has even topped ChromeOS to become the fourth most widely used OS around the globe.
-
KDE’s Plasma 6 Officially Available
KDE’s Plasma 6.0 "Megarelease" has happened, and it's brimming with new features, polish, and performance.
-
Latest Version of Tails Unleashed
Tails 6.0 is based on Debian 12 and includes GNOME 43.
-
KDE Announces New Slimbook V with Plenty of Power and KDE’s Plasma 6
If you're a fan of KDE Plasma, you'll be thrilled to hear they've announced a new Slimbook with an AMD CPU and the latest version of KDE Plasma desktop.
-
Monthly Sponsorship Includes Early Access to elementary OS 8
If you want to get a glimpse of what's in the pipeline for elementary OS 8, just set up a monthly sponsorship to help fund its continued existence.
-
DebConf24 to be Held in South Korea
Busan will be the location of the latest DebConf running July 28 through August 4
-
Fedora Unleashes Atomic Desktops
Fedora has combined its solid distribution with rpm-ostree system to make it possible to deliver a new family of Fedora spins, called Fedora Atomic Desktops.
-
Bootloader Vulnerability Affects Nearly All Linux Distributions
The developers of shim have released a version to fix numerous security flaws, including one that could enable remote control execution of malicious code under certain circumstances.