CVE-2021-25914: 
JavaScript vulnerability analysis and mitigation

Prototype pollution vulnerability in 'object-collider' versions 1.0.0 through 1.0.3 was discovered and disclosed on March 1, 2021. The vulnerability affects the object-collider package and allows attackers to cause a denial of service and potentially execute remote code (NVD, Mend).

The vulnerability exists in the collide() function which accepts four arguments. The function lacks proper validation on the values passed into the args2 argument, allowing attackers to supply malicious values by including the __proto__ property. Without validation to check whether the assigned argument is the Object's own property, properties can be directly assigned to new objects, leading to Object prototype pollution. The vulnerability has been assigned a CVSS v3.1 base score of 9.8 (CRITICAL) and is classified as CWE-1321 (Improperly Controlled Modification of Object Prototype Attributes) (Mend).

The successful exploitation of this vulnerability can lead to denial of service conditions and potentially remote code execution. When exploited, attackers can pollute the Object prototype, causing unexpected behavior in the application by modifying properties that would affect all objects (Mend).

A proof of concept exploit has been published demonstrating how the vulnerability can be triggered. The exploit involves using JSON.parse to create a payload with a __proto__ property, which when processed by the vulnerable collide() function, results in prototype pollution (Mend).

The recommended mitigation is to upgrade to version 1.0.4 or later, which includes a fix for this vulnerability. The fix involves adding validation to prevent __proto__ property manipulation, as demonstrated in the patch (GitHub Patch).