CVE-2025-67489: @vitejs/plugin-rsc Remote Code Execution through unsafe dynamic imports in RSC server function APIs on development server

Should you act?

Critical and remotely reachable

No known exploitation yet, but it is network-reachable without credentials. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.

• Not in CISA KEV, but CISA’s SSVC assessment records a public proof-of-concept, so attack code exists.
• EPSS 0.8%, percentile 57: FIRST’s model estimates a 0.8% chance of exploitation activity in the next 30 days, higher than 57% of all scored CVEs (moderate). EPSS is a probability, not a verdict.
• Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
• Only applies if your dependency tree includes @vitejs/plugin-rsc (npm) <= 0.5.5, fixed in 0.5.6. Check your lockfile, including transitive dependencies.

What it is

@vitejs/plugin-rs provides React Server Components (RSC) support for Vite. Versions 0.5.5 and below are vulnerable to arbitrary remote code execution on the development server through unsafe dynamic imports in server function APIs (loadServerAction, decodeReply, decodeAction) when integrated into RSC applications that expose server function endpoints. Attackers with network access to the development server can read/modify files, exfiltrate sensitive data (source code, environment variables, credentials), or pivot to other internal services. While this affects development servers only, the risk increases when using vite --host to expose the server on all network interfaces. This issue is fixed in version 0.5.6.

From the GitHub advisory

Summary

Arbitrary Remote Code Execution on development server via unsafe dynamic imports in @vitejs/plugin-rsc server function APIs (loadServerAction, decodeReply, decodeAction) when integrated into RSC applications that expose server function endpoints.

Impact

Attackers with network access to the development server can execute arbitrary JavaScript code with Node.js privileges, allowing them to read/modify files, exfiltrate sensitive data (source code, environment variables, credentials), or pivot to other internal services. While this affects development servers only, the risk increases when using vite --host to expose the server on all network interfaces.

Details

Weakness type: CWE-94.

Product: @vitejs/plugin-rsc (npm) · Assigned by: GitHub_M · Published: 2025-12-09

Affected and fixed versions

Severity scores

• Attack vector: network (remotely reachable)
• Attack complexity: low
• Privileges required: none (no login)
• User interaction: none
• Scope: unchanged

CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.

Exploitation and urgency

• CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
• CISA SSVC assessment: exploitation poc, automatable yes, technical impact total.
• FIRST EPSS (model of 2026-10-21): 0.81% probability of exploitation activity in the next 30 days; percentile 57.

Timeline

• 2025-12-08 — GitHub-reviewed advisory GHSA-j76j-5p5g-9wfr published (critical)
• 2025-12-09 — CVE record published by GitHub_M
• 2025-12-10 — CVE record last updated

Sources and references

Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.

Vulnerability records

1. GitHub Advisory GHSA-j76j-5p5g-9wfr github.com
2. CVE.org record CVE-2025-67489 cve.org
3. NVD entry CVE-2025-67489 nvd.nist.gov

Other references from the CVE record and advisory

1. github.com github.com
2. github.com github.com

Critical npm advisories · Today’s Security Digest