CVE-2025-69256
HIGHCVE-2025-69256 is a high-severity (CVSS 7.5) CWE-77 vulnerability in serverless. O3 Security confirms whether CVE-2025-69256 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
serverless MCP Server vulnerable to command injection in list-projects tool
Blast Radius
Weekly download volume for affected packages — a proxy for how broadly this vulnerability is deployed.
serverlessnpmDescription
The Serverless Framework is a framework for using AWS Lambda and other managed cloud services to build applications. Starting in version 4.29.0 and prior to version 4.29.3, a command injection vulnerability exists in the Serverless Framework's built-in MCP server package (@serverless/mcp). This vulnerability only affects users of the experimental MCP server feature (serverless mcp), which represents less than 0.1% of Serverless Framework users. The core Serverless Framework CLI and deployment functionality are not affected. The vulnerability is caused by the unsanitized use of input parameters within a call to child_process.exec, enabling an attacker to inject arbitrary system commands. Successful exploitation can lead to remote code execution under the server process's privileges. The server constructs and executes shell commands using unvalidated user input directly within command-line strings. This introduces the possibility of shell metacharacter injection (|, >, &&, etc.). Version 4.29.3 fixes the issue.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | serverless | ≥ 4.29.0&&< 4.29.3 | 4.29.3 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for serverless. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update serverless to 4.29.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-69256 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2025-69256 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2025-69256. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2025-69256 in your dependencies?
O3 detects CVE-2025-69256 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.