Known exploited · Meta Platforms
CVE-2025-55177: Meta Platforms WhatsApp Incorrect Authorization Vulnerability
What it is
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.
- Vendor
- Meta Platforms
- Product
- Added to KEV
- September 2, 2025
- CISA due date
- September 23, 2025
- Ransomware use
- Unknown
- Weakness
- CWE-863: Incorrect Authorization
What CISA requires
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Forensic triage
No
What to do now
- Find every instance of WhatsApp you run, including the forgotten ones, and check its version against the vendor advisory.
- Apply the vendor's fix or mitigation, before September 23, 2025 if you are bound by CISA's deadline, sooner if it faces the internet.
- Assume it was tried against you already: look for signs of exploitation from the date it was added, not from the day you patched.
References
H2 Security
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Start freeSource: CISA Known Exploited Vulnerabilities Catalog (public domain), catalog version 2026.10.01.