CVE-2016-1660

What it actually does

Mishandling of assertions in WTF::BitArray and WTF::double_conversion::Vector classes results in an out-of-bounds write condition when processing crafted web content.

Why it matters to the business

Attackers can crash browsers or potentially execute arbitrary code on user systems, leading to data theft, session hijacking, or further compromise of endpoint devices across the organization.

How an attack unfolds

An attacker hosts a malicious website containing specially crafted content that triggers the assertion mishandling when rendered by the vulnerable browser engine; visiting users trigger the flaw, enabling denial of service or code execution.

How to fix it

Upgrade affected browser installations to version 50.0.2661.94 or later and ensure automatic updates are enabled for all supported products.

How to confirm the fix worked

Verify browser version numbers meet or exceed the fixed release; test rendering of known trigger patterns in isolated environments and confirm absence of assertion failures.

Typical attack path

1. Attacker prepares a crafted webpage exploiting the assertion flaw
2. Victim is lured to visit the page via phishing or compromised site
3. Browser renders the page and encounters the out-of-bounds write
4. Attacker gains control or causes denial of service in the renderer process

How to detect it

Review browser crash logs and renderer process dumps for patterns matching assertion failures or out-of-bounds memory access; correlate with web proxy logs showing visits to suspicious domains around the time of anomalies.

What your security team should do

• Prioritize patching all browser instances to the fixed version immediately
• Disable unnecessary browser extensions that may increase attack surface
• Monitor for unusual browser crashes or renderer process anomalies
• Educate users on avoiding untrusted websites