CVE-2026-23869Public exploitNetwork attack vector

Service interruption via crafted request deserialization

Published Apr 8, 2026 · Updated Apr 8, 2026

Denial of service in affected React Server Components 19.x packages allows remote attackers to interrupt server responses. The Server Function endpoint deserializer accepts a crafted HTTP payload that drives excessive CPU consumption for up to one minute before throwing a catchable error. Exposure requires a server-side application using a framework, bundler, or plugin that supports React Server Components; client-only React applications are unaffected.

CVSS severity7.5
High
EPSS probability1.55%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Denial of service in affected React Server Components 19.x packages allows remote attackers to interrupt server responses. The Server Function endpoint deserializer accepts a crafted HTTP payload that drives excessive CPU consumption for up to one minute before throwing a catchable error. Exposure requires a server-side application using a framework, bundler, or plugin that supports React Server Components; client-only React applications are unaffected.

The record

CVE
CVE-2026-23869
Published
Apr 8, 2026
Updated
Apr 8, 2026
Vendor
Meta Platforms, Inc.
Product
react-server-dom-parcel
Classifications
CWE-502, CWE-770, CWE-400, T1499.003
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 8, 2026CVE publishedPublication date reported by the CVE source.
  2. Apr 8, 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 <=19.0.4
  2. Affected versionversion=19.1.0 <=19.1.5
  3. Affected versionversion=19.2.0 <=19.2.4

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Meta Platforms, Inc. · react-server-dom-parcelversion=19.0.0 <=19.0.4; version=19.1.0 <=19.1.5; version=19.2.0 <=19.2.4
Meta Platforms, Inc. · react-server-dom-turbopackversion=19.0.0 <=19.0.4; version=19.1.0 <=19.1.5; version=19.2.0 <=19.2.4
Meta Platforms, Inc. · react-server-dom-webpackversion=19.0.0 <=19.0.4; version=19.1.0 <=19.1.5; version=19.2.0 <=19.2.4

Published CVSS scores

7.5Facebook, Inc.CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
7.5redhat-SADPCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/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 IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-502Deserialization of Untrusted Data
CWE-770Allocation of Resources Without Limits or Throttling
CWE-400Uncontrolled Resource Consumption
T1499.003Application Exhaustion Flood

Public exploit references

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

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo