CVE-2025-67779
Description
A flaw was found in React Server Components. This vulnerability allows a denial of service via unsafe deserialization of payloads from HTTP (Hypertext Transfer Protocol) requests to Server Function endpoints. A malicious HTTP request can be crafted and sent to any App Router endpoint that, when deserialized, can cause the server process to hang and consume CPU. This can result in denial of service.
This CVE has been issued as a complete fix for CVE-2025-55184 which was incomplete with initial fix.
Statement
It was found that the fix addressing CVE-2025-55184 in React Server Components was incomplete and did not fully prevent denial of service attacks in all payload types. A complete fix has been issued under this CVE-2025-67779.
Additionally, no Red Hat software includes the directly affected React Server Components packages (react-server-dom-parcel, react-server-dom-turbopack, react-server-dom-webpack). However, the reference implementation of React Server Components is used by other projects such as Next.js. The packages listed here include Next.js as a dependency, but our analysis indicates that they are not affected by the vulnerability as they do not use the App Router functionality that exposes endpoints serving the vulnerable protocol.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 7.5 | N/A | N/A |
| Attack Vector | Network | N/A | N/A |
| Attack Complexity | Low | N/A | N/A |
| Privileges Required | None | N/A | N/A |
| User Interaction | None | N/A | N/A |
| Scope | Unchanged | N/A | N/A |
| Confidentiality | None | N/A | N/A |
| Integrity Impact | None | N/A | N/A |
| Availability Impact | High | N/A | N/A |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Understanding the Weakness (CWE)
Integrity
Technical Impact: Modify Application Data; Unexpected State
Attackers can modify unexpected objects or data that was assumed to be safe from modification. Deserialized data or code could be modified without using the provided accessor functions, or unexpected functions could be invoked.
Availability
Technical Impact: DoS: Resource Consumption (CPU)
If a function is making an assumption on when to terminate, based on a sentry in a string, it could easily never terminate.
Other
Technical Impact: Varies by Context
The consequences can vary widely, because it depends on which objects or methods are being deserialized, and how they are used. Making an assumption that the code in the deserialized object is valid is dangerous and can enable exploitation. One example is attackers using gadget chains to perform unauthorized actions, such as generating a shell.
Frequently Asked Questions
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