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GHSA-p9pc-299p-vxgp CVE-2020-7608 SNYK-JS-YARGSPARSER-560381

yargs-parser Vulnerable to Prototype Pollution

Medium npm
Severity
5.3 / 10
Medium · CVSS 3.1
Exploit chance (EPSS)
0.51%
Chance of exploitation in the next 30 days. Higher than 43.86% of scored vulnerabilities.
Known exploited
No
Not in CISA's catalog
Weakness
CWE-1321 Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')
CWE-915 Improperly Controlled Modification of Dynamically-Determined Object Attributes
Fix
13.1.2
Upgrade yargs-parser to this version or later

Description

Affected versions of yargs-parser are vulnerable to prototype pollution. Arguments are not properly sanitized, allowing an attacker to modify the prototype of Object, causing the addition or modification of an existing property that will exist on all objects.
Parsing the argument --foo.__proto__.bar baz' adds a bar property with value baz to all objects. This is only exploitable if attackers have control over the arguments being passed to yargs-parser.

Recommendation

Upgrade to versions 13.1.2, 15.0.1, 18.1.1 or later.

Affected versions

npm

PackageVulnerableFixed in
yargs-parser
>= 6.0.0, < 13.1.2
13.1.2
yargs-parser
>= 14.0.0, < 15.0.1
15.0.1
yargs-parser
>= 16.0.0, < 18.1.1
18.1.1
yargs-parser
< 5.0.1
5.0.1

How to fix

Move to the fixed version or later with your package manager, update the lockfile, and run your tests. If the package only arrives through another dependency, upgrade that dependency first. If none of its releases pulls a fixed version yet, force the version with your package manager's override.

yargs-parser npm → 13.1.2

npm
npm install yargs-parser@13.1.2
yarn
yarn add yargs-parser@13.1.2
pnpm
pnpm add yargs-parser@13.1.2

Severity breakdown

CVSS 3.1 5.3

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L

Attack vector
Local
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
Low
Availability
Low

Weakness

CWE-1321: Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')

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.

How to prevent it
  • Implementation: By freezing the object prototype first (for example, Object.freeze(Object.prototype)), modification of the prototype becomes impossible.
  • Architecture and Design: By blocking modifications of attributes that resolve to object prototype, such as proto or prototype, this weakness can be mitigated.
  • Implementation: When handling untrusted objects, validating using a schema can be used.
  • Implementation: By using an object without prototypes (via Object.create(null) ), adding object prototype attributes by accessing the prototype via the special attributes becomes impossible, mitigating this weakness.
  • Implementation: Map can be used instead of objects in most cases. If Map methods are used instead of object attributes, it is not possible to access the object prototype or modify it.

CWE-915: Improperly Controlled Modification of Dynamically-Determined Object Attributes

The product receives input from an upstream component that specifies multiple attributes, properties, or fields that are to be initialized or updated in an object, but it does not properly control which attributes can be modified.

How to prevent it
  • Implementation: If available, use features of the language or framework that allow specification of allowlists of attributes or fields that are allowed to be modified. If possible, prefer allowlists over denylists. For applications written with Ruby on Rails, use the attr_accessible (allowlist) or attr_protected (denylist) macros in each class that may be used in mass assignment.
  • Architecture and Design, Implementation: If available, use the signing/sealing features of the programming language to assure that deserialized data has not been tainted. For example, a hash-based message authentication code (HMAC) could be used to ensure that data has not been modified.
  • Implementation: For any externally-influenced input, check the input against an allowlist of internal object attributes or fields that are allowed to be modified.
  • Implementation, Architecture and Design: Refactor the code so that object attributes or fields do not need to be dynamically identified, and only expose getter/setter functionality for the intended attributes.

References

Timeline

  1. Published
  2. Last updated by the source
  3. Latest EPSS score
AdvisorySeverityWhy it's related
GHSA-6wvx-3r32-xmcg
Forge: Prototype Pollution in forge.http cookie handling via a malicious Set-Cookie
Medium Same weakness, CWE-1321
GHSA-7648-jmwf-vw7j
systeminformation has prototype pollution in `networkStats()` via the interface name
Medium Same weakness, CWE-1321
GHSA-m2m5-rw3w-cwmj
ApostropheCMS: Client-side Prototype Pollution in apos.http.parseQuery leading to DOM-based XSS against authenticated users
Medium Same weakness, CWE-1321
GHSA-j5rq-xfvr-p969
ApostropheCMS: Authenticated projection-exclusion prototype-member deletion in @apostrophecms/db-connect causes process-wide denial of service
High Same weakness, CWE-1321
GHSA-97rh-rhh2-7vjv
Payload: Remote Code Execution through first-register
High Same weakness, CWE-1321
GHSA-4q55-j62x-fr9h
devalue: Malformed null-prototype object keys bypass __proto__ rejection via property-key coercion
Medium Same weakness, CWE-1321
GHSA-x97p-jq2g-jp4f
Axios: Prototype Pollution Gadget in axios toFormData Options
High Same weakness, CWE-1321
GHSA-vh66-26gq-q6x8
Axios: Prototype pollution gadget in fetch adapter can alter outbound requests
Medium Same weakness, CWE-1321
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