CVE-2024-0742

What it actually does

An incorrect timestamp check allows page-loaded content to trigger or dismiss browser prompts and dialogs without the intended post-load input protection delay.

Why it matters to the business

Users on unpatched browsers may unintentionally approve permissions, dismiss warnings, or perform actions that weaken security controls during normal web browsing.

How an attack unfolds

An attacker hosts a webpage that immediately presents a prompt or dialog after load; due to the timestamp flaw the user's first interaction can activate or dismiss it, bypassing the intended protection and leading to unintended consent or action.

How to fix it

Upgrade Firefox to version 122 or later, Firefox ESR to 115.7 or later, and Thunderbird to 115.7 or later. Apply vendor updates as soon as they become available for all affected Mozilla products and downstream distributions.

How to confirm the fix worked

Confirm browser and Thunderbird versions are at or above the fixed releases listed by Mozilla; retest prompt timing behavior on a freshly loaded page to verify the protection delay is enforced.

Typical attack path

1. Attacker crafts and hosts a malicious webpage containing prompt or dialog triggers
2. Victim visits the page with an affected browser version
3. Page content loads and immediately attempts to activate a prompt or dialog
4. User's natural first click or keypress unintentionally interacts with the prompt due to missing timestamp protection
5. Unintended permission grant, dismissal, or action occurs

How to detect it

Review web proxy or browser telemetry logs for visits to domains known to host exploit pages; look for rapid prompt-related DOM events immediately after page load in forensic browser artifact analysis.

What your security team should do

• Prioritize patching all Firefox, Firefox ESR, and Thunderbird instances to the fixed versions
• Monitor Mozilla release channels for any delayed or additional fixes
• Educate users on verifying browser version and applying updates promptly
• Review browser prompt-related security policies and consider additional UI hardening where feasible