# CVE-2026-23864: React Server Components have multiple Denial of Service Vulnerabilities > Attackers can cause server crashes or resource exhaustion in React Server Components applications by sending crafted HTTP requests to Server Function endpoints. - **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`) - **Exploited in the wild:** Not known - **Login needed:** Not needed - **Attackable:** Over the internet - **Victim action needed:** Not needed - **Fix available:** Yes - **Published:** 26 Jan 2026 - **Updated:** 15 Jul 2026 - **Also known as:** GHSA-83fc-fqcc-2hmg ## What is CVE-2026-23864? CVE-2026-23864 is a high-severity denial of service vulnerability in Meta react-server-dom-parcel, published on 26 Jan 2026. An attacker can exploit it over the internet without logging in, with no action from the victim. ### Official description Multiple denial of service vulnerabilities exist in React Server Components, affecting the following packages: react-server-dom-parcel, react-server-dom-turbopack, react-server-dom-webpack. The vulnerabilities are triggered by sending specially crafted HTTP requests to Server Function endpoints, and could lead to server crashes, out-of-memory exceptions or excessive CPU usage; depending on the vulnerable code path being exercised, the application configuration and application code. Strongly consider upgrading to the latest package versions to reduce risk and prevent availability issues in applications using React Server Components. Weakness: CWE-1284 (Improper Validation of Specified Quantity in Input), CWE-502 (Deserialization of Untrusted Data), CWE-400 (Uncontrolled Resource Consumption) ## Which versions are affected by CVE-2026-23864? 18 open source packages ship an affected version, including react-server-dom-parcel, react-server-dom-turbopack and react-server-dom-webpack. It affects 1 product. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `react-server-dom-parcel` | npm | From 19.0.0 | 19.0.4 | | `react-server-dom-parcel` | npm | From 19.0.0 | 19.0.4 | | `react-server-dom-parcel` | npm | From 19.1.0-canary-7130d0c6-20241212 | 19.1.5 | | `react-server-dom-parcel` | npm | From 19.1.0-canary-7130d0c6-20241212 | 19.1.5 | | `react-server-dom-parcel` | npm | From 19.2.0-canary-63779030-20250328 | 19.2.4 | | `react-server-dom-parcel` | npm | From 19.2.0-canary-63779030-20250328 | 19.2.4 | | `react-server-dom-turbopack` | npm | From 19.0.0 | 19.0.4 | | `react-server-dom-turbopack` | npm | From 19.0.0 | 19.0.4 | | `react-server-dom-turbopack` | npm | From 19.1.0-canary-7130d0c6-20241212 | 19.1.5 | | `react-server-dom-turbopack` | npm | From 19.1.0-canary-7130d0c6-20241212 | 19.1.5 | | `react-server-dom-turbopack` | npm | From 19.2.0-canary-63779030-20250328 | 19.2.4 | | `react-server-dom-turbopack` | npm | From 19.2.0-canary-63779030-20250328 | 19.2.4 | | `react-server-dom-webpack` | npm | From 19.0.0 | 19.0.4 | | `react-server-dom-webpack` | npm | From 19.0.0 | 19.0.4 | | `react-server-dom-webpack` | npm | From 19.1.0-canary-7130d0c6-20241212 | 19.1.5 | | `react-server-dom-webpack` | npm | From 19.1.0-canary-7130d0c6-20241212 | 19.1.5 | | `react-server-dom-webpack` | npm | From 19.2.0-canary-63779030-20250328 | 19.2.4 | | `react-server-dom-webpack` | npm | From 19.2.0-canary-63779030-20250328 | 19.2.4 | Products: Facebook React. ## How do I fix CVE-2026-23864? Upgrade react-server-dom-parcel to a fixed version for your release line: 19.0.4, 19.1.5 or 19.2.4. ## Is CVE-2026-23864 being exploited? There is no known exploitation of CVE-2026-23864 in the wild and no public exploit code. ## Other vulnerabilities in Meta react-server-dom-parcel - [CVE-2025-55182](https://insights.sbomify.com/CVE-2025-55182/): Meta React Server Components Remote Code Execution (critical 10.0, exploited in the wild) - [CVE-2025-55184](https://insights.sbomify.com/CVE-2025-55184/): Denial of Service Vulnerability in React Server Components (high 7.5) - [CVE-2025-67779](https://insights.sbomify.com/CVE-2025-67779/): Denial of Service Vulnerability in React Server Components (high 7.5) - [CVE-2018-6341](https://insights.sbomify.com/CVE-2018-6341/): Cross-Site Scripting in react-dom (medium 6.1) - [CVE-2025-55183](https://insights.sbomify.com/CVE-2025-55183/): Source Code Exposure Vulnerability in React Server Components (medium 5.3) ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2026-23864 and fix it if it is affected. What it is: CVE-2026-23864 is a high-severity denial of service vulnerability in Meta react-server-dom-parcel, published on 26 Jan 2026. An attacker can exploit it over the internet without logging in, with no action from the victim. Exploitation: There is no known exploitation of CVE-2026-23864 in the wild and no public exploit code. Affected packages and fixed versions: - react-server-dom-parcel (npm): affected from 19.0.0; fixed in 19.0.4 - react-server-dom-parcel (npm): affected from 19.0.0; fixed in 19.0.4 - react-server-dom-parcel (npm): affected from 19.1.0-canary-7130d0c6-20241212; fixed in 19.1.5 - react-server-dom-parcel (npm): affected from 19.1.0-canary-7130d0c6-20241212; fixed in 19.1.5 - react-server-dom-parcel (npm): affected from 19.2.0-canary-63779030-20250328; fixed in 19.2.4 - react-server-dom-parcel (npm): affected from 19.2.0-canary-63779030-20250328; fixed in 19.2.4 - react-server-dom-turbopack (npm): affected from 19.0.0; fixed in 19.0.4 - react-server-dom-turbopack (npm): affected from 19.0.0; fixed in 19.0.4 - react-server-dom-turbopack (npm): affected from 19.1.0-canary-7130d0c6-20241212; fixed in 19.1.5 - react-server-dom-turbopack (npm): affected from 19.1.0-canary-7130d0c6-20241212; fixed in 19.1.5 - react-server-dom-turbopack (npm): affected from 19.2.0-canary-63779030-20250328; fixed in 19.2.4 - react-server-dom-turbopack (npm): affected from 19.2.0-canary-63779030-20250328; fixed in 19.2.4 Task: 1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies. 2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it. 3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead. 4. Run the tests and summarise what changed and why. 5. If nothing in the project is affected, say so and change nothing. Reference: https://insights.sbomify.com/CVE-2026-23864/ (Markdown: https://insights.sbomify.com/CVE-2026-23864/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2026-23864 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-23864 - OSV: https://osv.dev/vulnerability/CVE-2026-23864 --- From sbomify Insights: https://insights.sbomify.com/CVE-2026-23864/ Summaries are generated and may contain mistakes; the official description above is the record.