CVE-2025-55182: Meta React Server Components Remote Code Execution Vulnerability

Is it exploited?

Yes. CISA added it to the Known Exploited Vulnerabilities catalog on 5 Dec 2025, 2 days after the CVE record was published.

How likely is exploitation in the next 30 days?

99.8%

EPSS score, percentile 100 of all scored records

How severe?

10.0 Critical

CVSS v3.1 base score, given by the CNA

What should I do?

CISA deadline 12 Dec 2025. Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

The CVE record links no vendor advisory, patch or mitigation.

Which versions are affected?

Affected

• 19.0.0 through 19.0.0
• 19.1.0 through 19.1.1
• 19.2.0 through 19.2.0
• 19.0.0 through 19.0.0
• 19.1.0 through 19.1.1
• 19.2.0 through 19.2.0

and 3 more in the table below

Versions by product

Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

What to do

CISA due date for this action: 12 December 2025.

Advisories and patches

The CVE record links no vendor advisory, patch or mitigation.

Linked from CISA's catalog entry

• https://react.dev/blog/2025/12/03/critical-security-vulnerability-in-react-server-components
• https://github.com/vercel-labs/fix-react2shell-next?tab=readme-ov-file
• https://nvd.nist.gov/vuln/detail/CVE-2025-55182

Affected products and versions

As listed in the CVE record.

Versions not listed are: unaffected.

Versions not listed are: unaffected.

Versions not listed are: unaffected.

Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

About this vulnerability

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.

Summary: CISA's KEV catalog, as of 28 Oct 2026.

• CISA added CVE-2025-55182 to its Known Exploited Vulnerabilities (KEV) catalog on 5 Dec 2025.
• CISA marks it as known to be used in ransomware campaigns.
• The due date CISA sets for the required action is 12 Dec 2025.
• The CVE record was published on 3 Dec 2025, 2 days before it was added to KEV.
• The CVE record carries a CVSS v3.1 base score of 10.0 (Critical), given by its CNA.
• FIRST's EPSS model puts the probability of exploitation in the next 30 days at 99.8% (percentile 100), as of 28 Oct 2026.
• CISA's SSVC assessment in the CVE record: exploitation active, automatable yes, technical impact total.

Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026. About the data.

Description

A pre-authentication remote code execution vulnerability exists in React Server Components versions 19.0.0, 19.1.0, 19.1.1, and 19.2.0 including the following packages: react-server-dom-parcel, react-server-dom-turbopack, and react-server-dom-webpack. The vulnerable code unsafely deserializes payloads from HTTP requests to Server Function endpoints.

Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

Weakness

• CWE-502

CWE and CAPEC are maintained by MITRE; the entries are those named in the CVE record and the KEV entry.

Timeline

References

• facebook.com
• react.dev

More exploited Meta vulnerabilities

• CVE-2025-55177: Meta Platforms WhatsApp Incorrect Authorization Vulnerability (added 2 Sep 2025)
• CVE-2019-18426: WhatsApp Cross-Site Scripting Vulnerability (added 23 May 2022)
• CVE-2019-3568: WhatsApp VOIP Stack Buffer Overflow Vulnerability (added 19 Apr 2022)