CVE-2025-55182Known exploitationPublic exploitNetwork attack vector

Unauthenticated code execution via unsafe Flight deserialization

Published Dec 3, 2025 · Updated Aug 4, 2026

Unsafe deserialization in Meta React Server Components 19.0.0, 19.1.0, 19.1.1, and 19.2.0 allows remote attackers to execute code. The Flight decoder rebuilds attacker-controlled object references from multipart form fields, permitting prototype-chain traversal to the Function constructor. Any server application using an affected package with React Server Components support is exposed through crafted HTTP requests, even when it defines no Server Functions.

CVSS severity10.0
Critical
EPSS probability99.80%
Next 30 days · Sep 16, 2026
Known exploitationReported
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Unsafe deserialization in Meta React Server Components 19.0.0, 19.1.0, 19.1.1, and 19.2.0 allows remote attackers to execute code. The Flight decoder rebuilds attacker-controlled object references from multipart form fields, permitting prototype-chain traversal to the Function constructor. Any server application using an affected package with React Server Components support is exposed through crafted HTTP requests, even when it defines no Server Functions.

The record

CVE
CVE-2025-55182
Published
Dec 3, 2025
Updated
Aug 4, 2026
Vendor
Meta Platforms, Inc.
Product
react-server-dom-parcel
Classifications
CWE-502, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Dec 3, 2025CVE publishedPublication date reported by the CVE source.
  2. Dec 4, 2025Exploitation reportedEarth Lamia and Jackpot Panda exploitation attempts
  3. Dec 5, 2025Exploitation reportedCISA Known Exploited Vulnerabilities catalog inclusion
  4. Aug 4, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=19.0.0 <=19.0.0
  2. Affected versionversion=19.1.0 <=19.1.1
  3. Affected versionversion=19.2.0 <=19.2.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Meta Platforms, Inc. · react-server-dom-parcelversion=19.0.0 <=19.0.0; version=19.1.0 <=19.1.1; version=19.2.0 <=19.2.0
Meta Platforms, Inc. · react-server-dom-turbopackversion=19.0.0 <=19.0.0; version=19.1.0 <=19.1.1; version=19.2.0 <=19.2.0
Meta Platforms, Inc. · react-server-dom-webpackversion=19.0.0 <=19.0.0; version=19.1.0 <=19.1.1; version=19.2.0 <=19.2.0

Published CVSS scores

10.0MetaCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsShadowserver observations through Sep 16, 2026. Gaps indicate unavailable data.
Sep 10, 2026Sep 16, 2026
View daily counts
Reporting dayUnique IPs
Sep 10, 2026321
Sep 11, 2026564
Sep 12, 202657
Sep 13, 202657
Sep 14, 202682
Sep 15, 202681
Sep 16, 2026119
Latest reporting daySep 16, 2026
Latest daily unique IPs119
Prior 30-day average111.8
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationReported
Public exploitPublished

Weakness, pattern, technique

CWE-502Deserialization of Untrusted Data
T1190Exploit Public-Facing Application

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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