Dark Reading is part of the Informa Tech Division of Informa PLC

This site is operated by a business or businesses owned by Informa PLC and all copyright resides with them.Informa PLC's registered office is 5 Howick Place, London SW1P 1WG. Registered in England and Wales. Number 8860726.

Application Security //

Malware detection

4/22/2019
12:35 PM
Larry Loeb
Larry Loeb
Larry Loeb
50%
50%

Over 500 Million Chrome iOS Sessions Hijacked in Massive Malvertising Campaign

Confiant has spotted the known threat actor eGobbler back in action.

Confiant has spotted the known threat actor eGobbler back in action. This group is well-known for attempting its campaigns around holidays, which is when it assumes there will be increased consumer traffic.

But this go-around the group is exploiting a currently unpatched flaw in the Chrome for iOS browser, to bypass sandboxing and hijack user sessions. This means that iPhone and iPad users are directly targeted.

eGobbler has historically used the ".world" TLD for their landing media like pop-ups, but this campaign seems to be using ".site" TLDs for web-based content.

eGobbler's main session hijacking mechanism in this case, however, was pop-up based. This is a change in strategy since when a browser's pop-up blocker is working it will stop the pop-up from appearing. Session hijacking happens when a user is redirected to another site or landing page. Alternatively, a pop-up can appear that one can't exit out of. The served pages look like ads from well-known brands, but they aren't. If clicked, a malicious payload is then deployed to the user.

Confiant has said that they "discovered techniques that took advantage of iOS Chrome's detection around user activated pop-up detection, resulting in the circumvention of pop-up blocking." Since Chrome remains unpatched at the time of this writing, Confiant is not revealing the exact code details of how this is done. That the exploit is able to bypass that need for user interaction should be impossible according to the same-origin policy (as it pertains to cross-origin iframes).

Additionally, this exploit also completely circumvents the browser's anti-redirect functionality. The attacker no longer needs to even spawn a redirect in order to hijack the user session. This latest hijacking lasted six days and started on Saturday, April 6. Confiant say that it was composed of eight individual campaigns and over 30 fake creatives. While the targeting was primarily US based, European publishers saw significant impact as well.

Confiant thinks over 500 million user sessions were exposed to the hijacking. They also said that "With half a billion user sessions impacted, this is among the top three massive malvertising campaigns that we have seen in the last 18 months."

eGobble will typically use cloaked intermediate CDN domains as part of their ad delivery. The domains may sit behind at least a single layer of client-side fingerprinting.

There remains a question about whether some of the hijacking tricks that are being used on Chrome can also be applied to Apple's Safari. Until explicit details of the exploit are known, no solid answer can be made.

— Larry Loeb has written for many of the last century's major "dead tree" computer magazines, having been, among other things, a consulting editor for BYTE magazine and senior editor for the launch of WebWeek.

Comment  | 
Print  | 
More Insights
Comments
Newest First  |  Oldest First  |  Threaded View
News
A Startup With NSA Roots Wants Silently Disarming Cyberattacks on the Wire to Become the Norm
Kelly Jackson Higgins, Executive Editor at Dark Reading,  5/11/2021
Edge-DRsplash-10-edge-articles
Cybersecurity: What Is Truly Essential?
Joshua Goldfarb, Director of Product Management at F5,  5/12/2021
Commentary
3 Cybersecurity Myths to Bust
Etay Maor, Sr. Director Security Strategy at Cato Networks,  5/11/2021
Register for Dark Reading Newsletters
White Papers
Video
Cartoon Contest
Current Issue
2021 Top Enterprise IT Trends
We've identified the key trends that are poised to impact the IT landscape in 2021. Find out why they're important and how they will affect you today!
Flash Poll
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
CVE-2020-19924
PUBLISHED: 2021-05-18
In Boostnote 0.12.1, exporting to PDF contains opportunities for XSS attacks.
CVE-2020-20220
PUBLISHED: 2021-05-18
Mikrotik RouterOs prior to stable 6.47 suffers from a memory corruption vulnerability in the /nova/bin/bfd process. An authenticated remote attacker can cause a Denial of Service (NULL pointer dereference).
CVE-2020-20227
PUBLISHED: 2021-05-18
Mikrotik RouterOs stable 6.47 suffers from a memory corruption vulnerability in the /nova/bin/diskd process. An authenticated remote attacker can cause a Denial of Service due to invalid memory access.
CVE-2020-20245
PUBLISHED: 2021-05-18
Mikrotik RouterOs stable 6.46.3 suffers from a memory corruption vulnerability in the log process. An authenticated remote attacker can cause a Denial of Service due to improper memory access.
CVE-2020-20246
PUBLISHED: 2021-05-18
Mikrotik RouterOs stable 6.46.3 suffers from a memory corruption vulnerability in the mactel process. An authenticated remote attacker can cause a Denial of Service due to improper memory access.