All the vulnerabilities related to the version 5.0.3 of the package
Prototype Pollution in JSON5 via Parse Method
The parse
method of the JSON5 library before and including version 2.2.1
does not restrict parsing of keys named __proto__
, allowing specially crafted strings to pollute the prototype of the resulting object.
This vulnerability pollutes the prototype of the object returned by JSON5.parse
and not the global Object prototype, which is the commonly understood definition of Prototype Pollution. However, polluting the prototype of a single object can have significant security impact for an application if the object is later used in trusted operations.
This vulnerability could allow an attacker to set arbitrary and unexpected keys on the object returned from JSON5.parse
. The actual impact will depend on how applications utilize the returned object and how they filter unwanted keys, but could include denial of service, cross-site scripting, elevation of privilege, and in extreme cases, remote code execution.
This vulnerability is patched in json5 v2.2.2 and later. A patch has also been backported for json5 v1 in versions v1.0.2 and later.
Suppose a developer wants to allow users and admins to perform some risky operation, but they want to restrict what non-admins can do. To accomplish this, they accept a JSON blob from the user, parse it using JSON5.parse
, confirm that the provided data does not set some sensitive keys, and then performs the risky operation using the validated data:
const JSON5 = require('json5');
const doSomethingDangerous = (props) => {
if (props.isAdmin) {
console.log('Doing dangerous thing as admin.');
} else {
console.log('Doing dangerous thing as user.');
}
};
const secCheckKeysSet = (obj, searchKeys) => {
let searchKeyFound = false;
Object.keys(obj).forEach((key) => {
if (searchKeys.indexOf(key) > -1) {
searchKeyFound = true;
}
});
return searchKeyFound;
};
const props = JSON5.parse('{"foo": "bar"}');
if (!secCheckKeysSet(props, ['isAdmin', 'isMod'])) {
doSomethingDangerous(props); // "Doing dangerous thing as user."
} else {
throw new Error('Forbidden...');
}
If the user attempts to set the isAdmin
key, their request will be rejected:
const props = JSON5.parse('{"foo": "bar", "isAdmin": true}');
if (!secCheckKeysSet(props, ['isAdmin', 'isMod'])) {
doSomethingDangerous(props);
} else {
throw new Error('Forbidden...'); // Error: Forbidden...
}
However, users can instead set the __proto__
key to {"isAdmin": true}
. JSON5
will parse this key and will set the isAdmin
key on the prototype of the returned object, allowing the user to bypass the security check and run their request as an admin:
const props = JSON5.parse('{"foo": "bar", "__proto__": {"isAdmin": true}}');
if (!secCheckKeysSet(props, ['isAdmin', 'isMod'])) {
doSomethingDangerous(props); // "Doing dangerous thing as admin."
} else {
throw new Error('Forbidden...');
}
Babel vulnerable to arbitrary code execution when compiling specifically crafted malicious code
Using Babel to compile code that was specifically crafted by an attacker can lead to arbitrary code execution during compilation, when using plugins that rely on the path.evaluate()
or path.evaluateTruthy()
internal Babel methods.
Known affected plugins are:
@babel/plugin-transform-runtime
@babel/preset-env
when using its useBuiltIns
option@babel/helper-define-polyfill-provider
, such as babel-plugin-polyfill-corejs3
, babel-plugin-polyfill-corejs2
, babel-plugin-polyfill-es-shims
, babel-plugin-polyfill-regenerator
No other plugins under the @babel/
namespace are impacted, but third-party plugins might be.
Users that only compile trusted code are not impacted.
The vulnerability has been fixed in @babel/traverse@7.23.2
.
Babel 6 does not receive security fixes anymore (see Babel's security policy), hence there is no patch planned for babel-traverse@6
.
@babel/traverse
to v7.23.2 or higher. You can do this by deleting it from your package manager's lockfile and re-installing the dependencies. @babel/core
>=7.23.2 will automatically pull in a non-vulnerable version.@babel/traverse
and are using one of the affected packages mentioned above, upgrade them to their latest version to avoid triggering the vulnerable code path in affected @babel/traverse
versions:
@babel/plugin-transform-runtime
v7.23.2@babel/preset-env
v7.23.2@babel/helper-define-polyfill-provider
v0.4.3babel-plugin-polyfill-corejs2
v0.4.6babel-plugin-polyfill-corejs3
v0.8.5babel-plugin-polyfill-es-shims
v0.10.0babel-plugin-polyfill-regenerator
v0.5.3Prototype Pollution in Ajv
An issue was discovered in ajv.validate() in Ajv (aka Another JSON Schema Validator) 6.12.2. A carefully crafted JSON schema could be provided that allows execution of other code by prototype pollution. (While untrusted schemas are recommended against, the worst case of an untrusted schema should be a denial of service, not execution of code.)
Improper Privilege Management in shelljs
shelljs is vulnerable to Improper Privilege Management
Improper Privilege Management in shelljs
Output from the synchronous version of shell.exec()
may be visible to other users on the same system. You may be affected if you execute shell.exec()
in multi-user Mac, Linux, or WSL environments, or if you execute shell.exec()
as the root user.
Other shelljs functions (including the asynchronous version of shell.exec()
) are not impacted.
Patched in shelljs 0.8.5
Recommended action is to upgrade to 0.8.5.
https://huntr.dev/bounties/50996581-c08e-4eed-a90e-c0bac082679c/
If you have any questions or comments about this advisory: