CVE-2024-6614

What it actually does

A flaw in the frame iterator for WebAssembly frames allows it to enter an infinite loop when processing certain crafted or malformed frames, resulting in incorrect or incomplete stack traces.

Why it matters to the business

Browser or email client instability during Wasm execution may occur along with misleading diagnostic data, increasing support overhead; low exploitation likelihood and no known ransomware use reduce urgency despite widespread browser deployment.

How an attack unfolds

An attacker embeds a specially crafted WebAssembly module in a web page that triggers the frame iterator loop condition, causing the affected application to produce erroneous stack traces or hang when the page is visited.

How to fix it

Upgrade Firefox to version 128 or later and Thunderbird to version 128 or later.

How to confirm the fix worked

Verify application version is 128 or higher; test rendering of known triggering Wasm modules and confirm stack traces are generated without looping or errors.

Typical attack path

1. Craft malicious Wasm frames designed to loop the iterator
2. Host the frames inside a web page or email content
3. Lure victim to load the content in an affected browser or client
4. Trigger iteration over the frames during execution or error handling
5. Obtain incorrect stack trace or induce application instability

How to detect it

Review browser crash reports and stack trace logs for signs of repeated frame iteration or malformed Wasm handling in versions prior to 128; inspect web traffic or page content for unusual WebAssembly modules.

What your security team should do

• Prioritize updating all Firefox and Thunderbird instances to version 128 or later
• Monitor EPSS and KEV status for any future changes indicating increased risk
• Educate users to keep browsers and email clients updated automatically