CyberSecBulletin
CVE-2025-55184NVD status: Modified

react-server-dom-webpack: Deserialization of Untrusted Data

Published Updated By the CyberSecBulletin desk

CVE-2025-55184 is a high-severity deserialization of untrusted data vulnerability in react-server-dom-webpack from Meta, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected react-server-dom-webpack versions: 19.0.0 through 19.0.1; 19.1.0 through 19.1.2; 19.2.0 through 19.2.1. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 64.4% chance of exploitation within 30 days, which is in the top 0.75% of all scored CVEs.

Patch now

Exploitation in the next 30 days is more likely than not, according to EPSS.

What to do

  1. Update React to 19.0.2 or 19.1.3 or 19.2.2, whichever matches your release line, or a later version.
  2. Update Next.js to 14.2.35 or 15.0.7 or 15.1.11 or 15.2.8, whichever matches your release line, or a later version.
  3. Read the advisory on react.dev for workarounds and exact fixed builds.
  4. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
Metareact-server-dom-webpack19.0.0 through 19.0.1; 19.1.0 through 19.1.2; 19.2.0 through 19.2.1Not stated
Metareact-server-dom-turbopack19.0.0 through 19.0.1; 19.1.0 through 19.1.2; 19.2.0 through 19.2.1Not stated
Metareact-server-dom-parcel19.0.0 through 19.0.1; 19.1.0 through 19.1.2; 19.2.0 through 19.2.1Not stated
FacebookReact19.0.0 up to, but not including, 19.0.2; 19.1.0 up to, but not including, 19.1.3; 19.2.0 up to, but not including, 19.2.219.0.2, 19.1.3, 19.2.2
VercelNext.js13.3.0 up to, but not including, 14.2.35; 15.0.0 up to, but not including, 15.0.7; 15.1.0 up to, but not including, 15.1.11; 15.2.0 up to, but not including, 15.2.8; 15.3.0 up to, but not including, 15.3.8; 15.4.0 up to, but not including, 15.4.10; 15.5.0 up to, but not including, 15.5.9; 16.0.0 up to, but not including, 16.0.10; and 2 more ranges14.2.35, 15.0.7, 15.1.11, 15.2.8, 15.3.8, 15.4.10

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
NoneNo data is disclosed.
Integrity
NoneNothing can be modified.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. Scored by CNA (fb.com).

Official description

A pre-authentication denial of service vulnerability exists in React Server Components versions 19.0.0, 19.0.1 19.1.0, 19.1.1, 19.1.2, 19.2.0 and 19.2.1, 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, which can cause an infinite loop that hangs the server process and may prevent future HTTP requests from being served.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Deserialization of Untrusted Data

The product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.

How developers prevent this class of flaw

  • If available, use the signing/sealing features of the programming language to assure that deserialized data has not been tainted. For example, a hash-based message authentication code (HMAC) could be used to ensure that data has not been modified.
  • When deserializing data, populate a new object rather than just deserializing. The result is that the data flows through safe input validation and that the functions are safe.
  • Explicitly define a final object() to prevent deserialization.

More Deserialization of Untrusted Data vulnerabilities (CWE-502)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: poc, automatable: yes, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in react-server-dom-webpack

All react-server-dom-webpack vulnerabilities

Recent Deserialization of Untrusted Data vulnerabilities

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