Deserialization in Facebook React

CVE-2025-67779

It was found that the fix addressing CVE-2025-55184 in React Server Components was incomplete and does not prevent a denial of service attack in a specific case. React Server Components versions 19.0.2, 19.1.3 and 19.2.2 are affected, allowing unsafe deserialization of payloads from HTTP requests to Server Function endpoints. This can cause an infinite loop that hangs the server process and may prevent future HTTP requests from being served.

Vulnerability class: Insecure Deserialization

Published · last modified .

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.200 (97.4th percentile), scored .

Moderate probability of exploitation in the next 30 days — watch for active exploitation reports. 97th percentile — 97.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2025-67779: held from 0.203 to 0.200.

EPSS over last 30 days · oldest: 0.203 · newest: 0.200 · change: -0.003

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2025-67779?
CVE-2025-67779 is a high-severity vulnerability in Facebook React, classified under Deserialization of Untrusted Data. CVSS score: 7.5/10. Published 2025-12-12.
How severe is CVE-2025-67779?
High severity. CVSS v3 base score is 7.5 out of 10.