CVE-2025-55177
Published 2025-08-29 · Updated 2026-10-18 · Source cve-assign@fb.com
Summary
CVE-2025-55177 is a medium-severity (CVSS 5.4) vulnerability in Meta Platforms WhatsApp. CISA added it to the Known Exploited Vulnerabilities catalog on September 2, 2025, which means exploitation in the wild has been confirmed; US federal agencies had to remediate it by September 23, 2025. CISA does not currently list it as used in ransomware campaigns. Meta Platforms has 3 vulnerabilities in the KEV catalog, 0 of them linked to ransomware.
All 3 known-exploited Meta Platforms vulnerabilities →Description
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.
CVSS vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
CISA Known-Exploited Vulnerability
Product: Meta Platforms — WhatsApp
Name: Meta Platforms WhatsApp Incorrect Authorization Vulnerability
Date added: 2025-09-02 · Due: 2025-09-23
Required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

