mockjs prototype pollution

Summaryinfo

A vulnerability described as critical has been identified in mockjs. This affects an unknown part. Such manipulation leads to prototype pollution. This vulnerability is listed as CVE-2023-26158. The attack may be performed from remote. There is no available exploit. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in mockjs (unknown version). It has been rated as critical. Affected by this issue is an unknown code block. The manipulation with an unknown input leads to a prototype pollution vulnerability. Using CWE to declare the problem leads to CWE-1321. The product receives input from an upstream component that specifies attributes that are to be initialized or updated in an object, but it does not properly control modifications of attributes of the object prototype. Impacted is integrity, and availability. CVE summarizes:

All versions of the package mockjs are vulnerable to Prototype Pollution via the Util.extend function due to missing check if the attribute resolves to the object prototype. By adding or modifying attributes of an object prototype, it is possible to create attributes that exist on every object, or replace critical attributes with malicious ones. This can be problematic if the software depends on existence or non-existence of certain attributes, or uses pre-defined attributes of object prototype (such as hasOwnProperty, toString or valueOf). User controlled inputs inside the extend() method of the Mock.Handler, Mock.Random, Mock.RE.Handler or Mock.Util, will allow an attacker to exploit this vulnerability. Workaround By using a denylist of dangerous attributes, this weakness can be eliminated. Add the following line in the Util.extend function: js js if (["__proto__", "constructor", "prototype"].includes(name)) continue js // src/mock/handler.js Util.extend = function extend() { var target = arguments[0] || {}, i = 1, length = arguments.length, options, name, src, copy, clone if (length === 1) { target = this i = 0 } for (; i < length; i++) { options = arguments[i] if (!options) continue for (name in options) { if (["__proto__", "constructor", "prototype"].includes(name)) continue src = target[name] copy = options[name] if (target === copy) continue if (copy === undefined) continue if (Util.isArray(copy) || Util.isObject(copy)) { if (Util.isArray(copy)) clone = src && Util.isArray(src) ? src : [] if (Util.isObject(copy)) clone = src && Util.isObject(src) ? src : {} target[name] = Util.extend(clone, copy) } else { target[name] = copy } } } return target }

The weakness was presented 12/08/2023. The advisory is available at github.com. This vulnerability is handled as CVE-2023-26158 since 02/20/2023. The technical details are unknown and an exploit is not available. This vulnerability is assigned to T1059 by the MITRE ATT&CK project.

Upgrading eliminates this vulnerability.

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Productinfo

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• mockjs

CPE 2.3info

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• 🔍

CPE 2.2info

• 🔍
• 🔍

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