CVE-2025-55177 Meta Platforms WhatsApp: login or permission bypass
In plain words: A door that should be locked is not: part of the system can be reached without a valid login or permission. The attacker gets in as a user or administrator without knowing a password.
Confirmed exploited by CISA on · US federal patch deadline Sep 23, 2025
What to do
- Install Meta Platforms's security update for WhatsApp. If no update exists, follow the vendor's workaround or stop using the product until one ships.
- Keep a list of every internet-facing server you run so nothing is forgotten.
- Patch anything in this catalog first, ahead of normal patch cycles.
- Put admin and file-transfer apps behind a VPN or single sign-on instead of the open internet.
Who is affected
Work IT. Aimed mostly at company systems — you are affected through the companies you use, not your own phone.
What's at risk: Mass data theft and ransomware: a single flaw in a file-transfer or email server has exposed thousands of organisations at once.
The details
- Official name
- Meta Platforms WhatsApp Incorrect Authorization Vulnerability
- Product
- Meta Platforms WhatsApp
- CISA description
- Meta Platforms WhatsApp contains an incorrect authorization vulnerability due to an incomplete authorization of linked device synchronization messages. This vulnerability could allow an unrelated user to trigger processing of content from an arbitrary URL on a target’s device.
- Type of flaw
- Login or permission bypass (CWE-863)
- Confirmed exploited
- Sep 2, 2025
- US federal patch deadline
- Sep 23, 2025
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Answering about CVE-2025-55177 ·
Questions about CVE-2025-55177
Is CVE-2025-55177 being exploited?
Yes. CISA added CVE-2025-55177 to its Known Exploited Vulnerabilities catalog on Sep 2, 2025, which means there is reliable evidence of real-world attacks.
How do I fix CVE-2025-55177?
Install Meta Platforms's security update for WhatsApp. If no update exists, follow the vendor's workaround or stop using the product until one ships. Keep a list of every internet-facing server you run so nothing is forgotten.
Am I affected by CVE-2025-55177?
Only if you use Meta Platforms WhatsApp. Aimed mostly at company systems — you are affected through the companies you use, not your own phone.