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2a02:26f0:ef:299::ecd
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Submitted URL: https://snyk.io/vuln/SNYK-JS-INIPARSER-564122
Effective URL: https://security.snyk.io/vuln/SNYK-JS-INIPARSER-564122
Submission: On June 29 via api from NL — Scanned from FR
Effective URL: https://security.snyk.io/vuln/SNYK-JS-INIPARSER-564122
Submission: On June 29 via api from NL — Scanned from FR
Form analysis
2 forms found in the DOM<form id="mktoForm_1461" style="display: none; font-family: Helvetica, Arial, sans-serif; font-size: 13px; color: rgb(51, 51, 51); width: 1px;" novalidate="novalidate" class="mktoForm mktoHasWidth mktoLayoutLeft">
<style type="text/css">
.mktoForm .mktoButtonWrap.mktoSimple .mktoButton {
color: #fff;
border: 1px solid #75ae4c;
padding: 0.4em 1em;
font-size: 1em;
background-color: #99c47c;
background-image: -webkit-gradient(linear, left top, left bottom, from(#99c47c), to(#75ae4c));
background-image: -webkit-linear-gradient(top, #99c47c, #75ae4c);
background-image: -moz-linear-gradient(top, #99c47c, #75ae4c);
background-image: linear-gradient(to bottom, #99c47c, #75ae4c);
}
.mktoForm .mktoButtonWrap.mktoSimple .mktoButton:hover {
border: 1px solid #447f19;
}
.mktoForm .mktoButtonWrap.mktoSimple .mktoButton:focus {
outline: none;
border: 1px solid #447f19;
}
.mktoForm .mktoButtonWrap.mktoSimple .mktoButton:active {
background-color: #75ae4c;
background-image: -webkit-gradient(linear, left top, left bottom, from(#75ae4c), to(#99c47c));
background-image: -webkit-linear-gradient(top, #75ae4c, #99c47c);
background-image: -moz-linear-gradient(top, #75ae4c, #99c47c);
background-image: linear-gradient(to bottom, #75ae4c, #99c47c);
}
</style>
<div class="mktoButtonRow"><span class="mktoButtonWrap mktoSimple" style="margin-left: 120px;"><button type="submit" class="mktoButton">Submit</button></span></div><input type="hidden" name="formid" class="mktoField mktoFieldDescriptor"
value="1461"><input type="hidden" name="munchkinId" class="mktoField mktoFieldDescriptor" value="677-THP-415">
</form>
<form style="display: none; font-family: Helvetica, Arial, sans-serif; font-size: 13px; color: rgb(51, 51, 51); visibility: hidden; position: absolute; top: -500px; left: -1000px; width: 1600px;" novalidate="novalidate"
class="mktoForm mktoHasWidth mktoLayoutLeft"></form>
Text Content
About Snyk 1. Snyk Vulnerability Database 2. npm 3. ini-parser PROTOTYPE POLLUTION AFFECTING INI-PARSER OPEN THIS LINK IN A NEW TAB PACKAGE, VERSIONS * -------------------------------------------------------------------------------- 4.4 medium * EXPLOIT MATURITY Proof of concept * ATTACK COMPLEXITY Low See more Do your applications use this vulnerable package? In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes. Test your applications * SNYK-ID SNYK-JS-INIPARSER-564122 * PUBLISHED 1 Apr 2020 * DISCLOSED 1 Apr 2020 * CREDIT JHU System Security Lab Report a new vulnerability Found a mistake? INTRODUCED: 1 APR 2020 CVE-2020-7617 Open this link in a new tab CWE-400 Open this link in a new tab First added by Snyk Share HOW TO FIX? There is no fixed version for ini-parser. OVERVIEW ini-parser is a package to parse .ini files. Affected versions of this package are vulnerable to Prototype Pollution. The library could be tricked into adding or modifying properties of Object.prototype using a __proto__ payload. POC var a = require("ini-parser"); a.parse('[__proto__]\ntoString=JHU'); console.log({}.toString); DETAILS Prototype Pollution is a vulnerability affecting JavaScript. Prototype Pollution refers to the ability to inject properties into existing JavaScript language construct prototypes, such as objects. JavaScript allows all Object attributes to be altered, including their magical attributes such as _proto_, constructor and prototype. An attacker manipulates these attributes to overwrite, or pollute, a JavaScript application object prototype of the base object by injecting other values. Properties on the Object.prototype are then inherited by all the JavaScript objects through the prototype chain. When that happens, this leads to either denial of service by triggering JavaScript exceptions, or it tampers with the application source code to force the code path that the attacker injects, thereby leading to remote code execution. There are two main ways in which the pollution of prototypes occurs: * Unsafe Object recursive merge * Property definition by path UNSAFE OBJECT RECURSIVE MERGE The logic of a vulnerable recursive merge function follows the following high-level model: merge (target, source) foreach property of source if property exists and is an object on both the target and the source merge(target[property], source[property]) else target[property] = source[property] When the source object contains a property named _proto_ defined with Object.defineProperty() , the condition that checks if the property exists and is an object on both the target and the source passes and the merge recurses with the target, being the prototype of Object and the source of Object as defined by the attacker. Properties are then copied on the Object prototype. Clone operations are a special sub-class of unsafe recursive merges, which occur when a recursive merge is conducted on an empty object: merge({},source). lodash and Hoek are examples of libraries susceptible to recursive merge attacks. PROPERTY DEFINITION BY PATH There are a few JavaScript libraries that use an API to define property values on an object based on a given path. The function that is generally affected contains this signature: theFunction(object, path, value) If the attacker can control the value of “path”, they can set this value to _proto_.myValue. myValue is then assigned to the prototype of the class of the object. TYPES OF ATTACKS There are a few methods by which Prototype Pollution can be manipulated: Type Origin Short description Denial of service (DoS) Client This is the most likely attack. DoS occurs when Object holds generic functions that are implicitly called for various operations (for example, toString and valueOf). The attacker pollutes Object.prototype.someattr and alters its state to an unexpected value such as Int or Object. In this case, the code fails and is likely to cause a denial of service. For example: if an attacker pollutes Object.prototype.toString by defining it as an integer, if the codebase at any point was reliant on someobject.toString() it would fail. Remote Code Execution Client Remote code execution is generally only possible in cases where the codebase evaluates a specific attribute of an object, and then executes that evaluation. For example: eval(someobject.someattr). In this case, if the attacker pollutes Object.prototype.someattr they are likely to be able to leverage this in order to execute code. Property Injection Client The attacker pollutes properties that the codebase relies on for their informative value, including security properties such as cookies or tokens. For example: if a codebase checks privileges for someuser.isAdmin, then when the attacker pollutes Object.prototype.isAdmin and sets it to equal true, they can then achieve admin privileges. AFFECTED ENVIRONMENTS The following environments are susceptible to a Prototype Pollution attack: * Application server * Web server HOW TO PREVENT 1. Freeze the prototype— use Object.freeze (Object.prototype). 2. Require schema validation of JSON input. 3. Avoid using unsafe recursive merge functions. 4. Consider using objects without prototypes (for example, Object.create(null)), breaking the prototype chain and preventing pollution. 5. As a best practice use Map instead of Object. FOR MORE INFORMATION ON THIS VULNERABILITY TYPE: Arteau, Oliver. “JavaScript prototype pollution attack in NodeJS application.” GitHub, 26 May 2018 REFERENCES * GitHub PR * Vulnerable Code PRODUCT * Snyk Open Source * Snyk Code * Snyk Container * Snyk Infrastructure as Code * Test with Github * Test with CLI RESOURCES * Vulnerability DB * Documentation * Disclosed Vulnerabilities * Blog * FAQs COMPANY * About * Jobs * Contact * Policies * Do Not Sell My Personal Information CONTACT US * Support * Report a new vuln * Press Kit * Events FIND US ONLINE * * * * TRACK OUR DEVELOPMENT * * © 2022 Snyk Limited Registered in England and Wales. Company number: 09677925 Registered address: Highlands House, Basingstoke Road, Spencers Wood, Reading, Berkshire, RG7 1NT. Submit