CVE-2024-6613

What it actually does

A flaw in the WASM frame iterator allows it to enter an infinite loop when processing certain frames, resulting in incorrect stack traces.

Why it matters to the business

May cause browser or email client instability when handling malicious web content, potentially leading to crashes or degraded performance.

How an attack unfolds

An attacker crafts a specially designed WebAssembly module embedded in a web page or email, which when processed by the affected application triggers the loop condition in the frame iterator.

How to fix it

Upgrade Firefox and Thunderbird to version 128 or later.

How to confirm the fix worked

Check the version of Firefox or Thunderbird is 128 or higher; attempt to reproduce with known triggering WASM if available.

Typical attack path

1. Deliver malicious WASM via web page or attachment
2. Trigger processing of the WASM frames
3. Induce infinite loop in iterator

How to detect it

Look for crashes or high CPU usage in Firefox/Thunderbird processes when accessing web content with WASM.

What your security team should do

• Update all instances of Firefox and Thunderbird to version 128 or newer
• Monitor for updates in related Mozilla products