Impact

The vulnerability exposes Aurelia application that uses aurelia-path package to parse a string. The majority of this will be Aurelia applications that employ the aurelia-router package. An example is this could allow an attacker to change the prototype of base object class Object by tricking an application to parse the following URL: https://aurelia.io/blog/?__proto__[asdf]=asdf

Patches

The problem should be patched in version 1.1.7. Any version earlier than this is vulnerable.

Workarounds

A partial work around is to free the Object prototype:

Object.freeze(Object.prototype)

References

• GHSA-3c9c-2p65-qvwv
• aurelia/path#44
• https://nvd.nist.gov/vuln/detail/CVE-2021-41097
• aurelia/path@7c4e235
• https://github.com/aurelia/path/releases/tag/1.1.7
• https://www.npmjs.com/package/aurelia-path