# React Server Components are Vulnerable to RCE Advisory record · `GHSA-fv66-9v8q-g76r` - **Identifiers:** `GHSA-fv66-9v8q-g76r` · `CVE-2025-55182` - **State:** Confirmed - **Severity:** CVSS 10.0 Critical - **Critical:** Yes: KEV, CVSS 9+, CVSS 7+ and EPSS - **Weakness (CWE):** [CWE-502](https://cwe.mitre.org/data/definitions/502.html) - **Tags:** [Insecure deserialization](https://agentprime.io/advisories/tag/deserialization.md) - **Published:** 3 Dec 2025 - **Updated:** 9 Dec 2025 - **Reviewed by a person:** No Published by the GitHub Advisory Database at 3 Dec 2025, 19:07 UTC. agentprime has not analysed this yet, so whether it affects any app is not known. ## Critical Critical, because: - In CISA’s KEV catalogue since 5 Dec 2025: it is known to be exploited. - CVSS score 10.0: 9.0 or more. - CVSS score 10.0 (7.0 or more) and EPSS 1.00 (0.1 or more): a high score and a real chance of exploitation in the next 30 days. How we decide what’s critical: ## Affected packages - `react-server-dom-webpack` (npm): affected `>=19.0.0, <19.0.1 || >=19.1.0, <19.1.2 || >=19.2.0, <19.2.1`; fixed in `19.0.1`, `19.1.2`, `19.2.1` - `react-server-dom-turbopack` (npm): affected `>=19.0.0, <19.0.1 || >=19.1.0, <19.1.2 || >=19.2.0, <19.2.1`; fixed in `19.0.1`, `19.1.2`, `19.2.1` - `react-server-dom-parcel` (npm): affected `>=19.0.0, <19.0.1 || >=19.1.0, <19.1.2 || >=19.2.0, <19.2.1`; fixed in `19.0.1`, `19.1.2`, `19.2.1` ## Not analysed yet We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check. ## Severity and exploitation - 10.0 Critical, CVSS 3.1: `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H`, from CNA (Meta) - **CISA KEV:** Listed since 5 Dec 2025: known to be exploited. CISA reports use in ransomware campaigns. - **EPSS:** 1.00, the 99th percentile, on 13 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days. ## Timeline - 3 Dec 2025, 15:48 UTC: [Published by the maintainers as a GitHub repository advisory](https://github.com/react/react/security/advisories/GHSA-fv66-9v8q-g76r) ## Sources - [GitHub Advisory Database: GHSA-fv66-9v8q-g76r](https://github.com/advisories/GHSA-fv66-9v8q-g76r) - [OSV: GHSA-fv66-9v8q-g76r](https://osv.dev/vulnerability/GHSA-fv66-9v8q-g76r) - - - - - - - - - - - - Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code. ## Check whether this affects you A Match means an installed version is in the affected range above. Most don’t affect the app; agentprime hasn’t analysed this one yet. - With the agentprime MCP server (), ask your agent to check the project: `check_lockfile` sends a lockfile, `check_packages` a list of installed packages, and both return the Matches and the upgrades that clear them. `get_advisory` returns this record. Setup: - In a browser: reads your lockfile in the browser, never uploading it. - Whether it touches your code, with file and line: the Claude Code plugin, - As JSON: , or `POST https://api.agentprime.io/v1/match` with your packages () --- The web page: . Everything for agents: .