Exploited· due 2025-12-12used in ransomware

CVE-2025-55182

Meta React Server Components

Meta React Server Components contains a remote code execution vulnerability that could allow unauthenticated remote code execution by exploiting a flaw in how React decodes payloads sent to React Server Function endpoints. Please note CVE-2025-66478 has been rejected, but it is associated with CVE-2025- 55182.

Exploitation status

  • CISA has confirmed this is being exploited in the wild. That is an observation of real attacks, not a prediction.
  • It is known to have been used in ransomware campaigns.
  • US federal civilian agencies are required to remediate it by 2025-12-12. That deadline does not bind private companies, but it is a reasonable benchmark for how urgently CISA views it.

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.

CISA’s wording, unedited.

Scoring

CVSS
Not yet scored

Dates

Published
2025-12-05
Added to KEV
2025-12-05
Remediation due
2025-12-12
Sources
CISA KEV