CVE-2025-55177 Meta Platforms WhatsApp Incorrect Authorization Vulnerability
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.
From the CISA KEV catalogue version 2026.11.06, with Cybergen analysis. Updated 6 Nov 2026.
Should You Worry?
- CISA confirmed exploitation in the wild and added it to the Known Exploited Vulnerabilities catalogue on 2 Sep 2025.
- Rated Medium severity (CVSS 5.4, scored by Vendor).
- It has been in the catalogue for 430 days. Systems still unpatched now have almost certainly been scanned for it.
What It Is
Incomplete authorization of linked device synchronization messages in WhatsApp for iOS prior to v2.25.21.73, WhatsApp Business for iOS v2.25.21.78, and WhatsApp for Mac v2.25.21.78 could have allowed an unrelated user to trigger processing of content from an arbitrary URL on a target’s device. We assess that this vulnerability, in combination with an OS-level vulnerability on Apple platforms (CVE-2025-43300), may have been exploited in a sophisticated attack against specific targeted users.
Affected Versions
| Product | Versions |
|---|---|
| Facebook WhatsApp Desktop for Mac | 2.22.25.2 to before 2.25.21.78 |
| Facebook WhatsApp Business for iOS | 2.22.25.2 to before 2.25.21.78 |
| Facebook WhatsApp for iOS | 2.22.25.2 to before 2.25.21.73 |
From the public CVE record, as supplied by the vendor. Always confirm against the vendor advisory.
What To Do Now
- 1
Find it
Search your asset inventory and external attack surface for Meta Platforms WhatsApp. Include cloud images, appliances and anything a supplier runs for you.
Attack Surface Management - 2
Fix it
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Vulnerability Management - 3
Hunt for compromise
If an affected system was reachable before you patched, assume it may have been hit. Check logs, new accounts, web shells and outbound connections from the date of exposure.
Incident Response - 4
Prove it is fixed
Rescan or test the system after patching. Upgrades that fail silently and forgotten secondary instances are common.
Penetration Testing
The Compliance Clock
General guidance, not legal advice. Your obligations depend on your sector, scope and jurisdiction.
Not Sure If You Are Exposed?
Our attack surface and vulnerability teams can check your internet-facing estate for CVE-2025-55177 and every other exploited flaw on the list.