Risk Letters

Exploited vulnerability

CVE-2025-55177

TLP:CLEAR

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.

Facts

  • Vendor: Meta Platforms
  • Product: WhatsApp
  • CVSS: 5.4
  • EPSS (probability of exploitation within 30 days): 13.5 %
  • On CISA's Known Exploited Vulnerabilities list since: 2 September 2025
  • First known exploitation: 2 September 2025
  • CISA's deadline for US federal agencies: 23 September 2025
  • Weakness: CWE-863
  • First seen by Risk Letters: 2 September 2025

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Data: NVD (public domain), CISA KEV, FIRST EPSS, MITRE ATT&CK, AlienVault OTX. NVD