CVE-2024-21413 Microsoft Office Outlook: software flaw
In plain words: A mistake in the software that attackers have found a way to abuse. Depends on the product — see the description and the vendor advisory.
Confirmed exploited by CISA on · US federal patch deadline Feb 27, 2025
What to do
- Install Microsoft's security update for Office Outlook. If no update exists, follow the vendor's workaround or stop using the product until one ships.
- Turn on automatic updates for the operating system and for Office, PDF and archive apps.
- Be careful with unexpected attachments — documents, .zip/.rar files and shortcuts are common bait.
- Use a normal (non-admin) account day to day and keep built-in protection like Microsoft Defender on.
Who is affected
Could reach you. This one is aimed at devices or apps of the kind people own.
What's at risk: Your files, saved passwords and accounts. Many of these let a program that is already running gain full administrator control.
The details
- Official name
- Microsoft Outlook Improper Input Validation Vulnerability
- Product
- Microsoft Office Outlook
- CISA description
- Microsoft Outlook contains an improper input validation vulnerability that allows for remote code execution. Successful exploitation of this vulnerability would allow an attacker to bypass the Office Protected View and open in editing mode rather than protected mode.
- Type of flaw
- Software flaw (CWE-20)
- Confirmed exploited
- Feb 6, 2025
- US federal patch deadline
- Feb 27, 2025
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Answering about CVE-2024-21413 ·
Questions about CVE-2024-21413
Is CVE-2024-21413 being exploited?
Yes. CISA added CVE-2024-21413 to its Known Exploited Vulnerabilities catalog on Feb 6, 2025, which means there is reliable evidence of real-world attacks.
How do I fix CVE-2024-21413?
Install Microsoft's security update for Office Outlook. If no update exists, follow the vendor's workaround or stop using the product until one ships. Turn on automatic updates for the operating system and for Office, PDF and archive apps.
Am I affected by CVE-2024-21413?
Only if you use Microsoft Office Outlook. This one is aimed at devices or apps of the kind people own.