Common Weakness Enumeration
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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.
CVE-2026-8161 (GCVE-0-2026-8161)
Vulnerability from cvelistv5 – Published: 2026-05-12 08:50 – Updated: 2026-05-12 12:32
VLAI
Title
multiparty vulnerable to Denial of Service via Prototype Pollution leading to Uncaught Exception
Summary
multiparty@4.2.3 and lower versions are vulnerable to denial of service via uncaught exception. By sending a multipart/form-data request with a field name that collides with an inherited Object.prototype property such as __proto__, constructor, or toString, the parser invokes .push() on the inherited prototype value rather than an array, throwing a TypeError that propagates as an uncaught exception and crashes the process. Impact: any service accepting multipart uploads via multiparty is affected. Workarounds: none. Upgrade to multiparty@4.3.0 or higher.
Severity
7.5 (High)
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
Assigner
References
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| multiparty | multiparty |
Affected:
0 , ≤ 4.2.3
(semver)
Unaffected: 4.3.0 (semver) |
Credits
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CVE-2026-9101 (GCVE-0-2026-9101)
Vulnerability from cvelistv5 – Published: 2026-05-20 16:18 – Updated: 2026-05-27 13:10
VLAI
Title
Prototype pollution in csv parsing
Summary
Prototype pollution in csv parsing logic during import can lead to untrusted file paths (but not arguments) entering shell.openExternal after specific user behavior leading to "1-click" command execution.
Severity
4.3 (Medium)
SSVC
Exploitation: none
Automatable: no
Technical Impact: total
CISA Coordinator (v2.0.3)
CWE
- CWE-1321 - Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')
Assigner
References
1 reference
| URL | Tags |
|---|---|
| https://jira.mongodb.org/browse/COMPASS-10657 | issue-tracking |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| MongoDB, Inc. | Compass |
Affected:
1.36.3
Affected: 1.36.4 Affected: 1.37.0 Affected: 1.38.0 Affected: 1.38.1 Affected: 1.38.2 Affected: 1.39.0 Affected: 1.39.1 Affected: 1.39.2 Affected: 1.39.3 Affected: 1.39.4 Affected: 1.40.0 Affected: 1.40.1 Affected: 1.40.2 Affected: 1.40.3 Affected: 1.40.4 Affected: 1.41.0 Affected: 1.42.0 Affected: 1.42.1 Affected: 1.42.2 Affected: 1.42.3 Affected: 1.42.5 Affected: 1.43.0 Affected: 1.43.1 Affected: 1.43.2 Affected: 1.43.3 Affected: 1.43.4 Affected: 1.43.5 Affected: 1.43.6 Affected: 1.44.0 Affected: 1.44.3 Affected: 1.44.4 Affected: 1.44.5 Affected: 1.44.6 Affected: 1.44.7 Affected: 1.45.0 Affected: 1.45.1 Affected: 1.45.2 Affected: 1.45.3 Affected: 1.45.4 Affected: 1.46.0 Affected: 1.46.1 Affected: 1.46.2 Affected: 1.46.3 Affected: 1.46.4 Affected: 1.46.5 Affected: 1.46.6 Affected: 1.46.7 Affected: 1.46.8 Affected: 1.46.9 Affected: 1.46.10 Affected: 1.46.11 Affected: 1.47.0 Affected: 1.47.1 Affected: 1.48.0 Affected: 1.48.1 Affected: 1.48.2 Affected: 1.49.0 Affected: 1.49.1 Affected: 1.49.2 Affected: 1.49.3 Affected: 1.49.4 Affected: 1.49.5 |
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Mitigation
Phase: Implementation
Description:
- By freezing the object prototype first (for example, Object.freeze(Object.prototype)), modification of the prototype becomes impossible.
Mitigation
Phase: Architecture and Design
Description:
- By blocking modifications of attributes that resolve to object prototype, such as proto or prototype, this weakness can be mitigated.
Mitigation
Phase: Implementation
Strategy: Input Validation
Description:
- When handling untrusted objects, validating using a schema can be used.
Mitigation
Phase: Implementation
Description:
- 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.
Mitigation
Phase: Implementation
Description:
- 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.
CAPEC-1: Accessing Functionality Not Properly Constrained by ACLs
In applications, particularly web applications, access to functionality is mitigated by an authorization framework. This framework maps Access Control Lists (ACLs) to elements of the application's functionality; particularly URL's for web apps. In the case that the administrator failed to specify an ACL for a particular element, an attacker may be able to access it with impunity. An attacker with the ability to access functionality not properly constrained by ACLs can obtain sensitive information and possibly compromise the entire application. Such an attacker can access resources that must be available only to users at a higher privilege level, can access management sections of the application, or can run queries for data that they otherwise not supposed to.
CAPEC-180: Exploiting Incorrectly Configured Access Control Security Levels
An attacker exploits a weakness in the configuration of access controls and is able to bypass the intended protection that these measures guard against and thereby obtain unauthorized access to the system or network. Sensitive functionality should always be protected with access controls. However configuring all but the most trivial access control systems can be very complicated and there are many opportunities for mistakes. If an attacker can learn of incorrectly configured access security settings, they may be able to exploit this in an attack.
CAPEC-77: Manipulating User-Controlled Variables
This attack targets user controlled variables (DEBUG=1, PHP Globals, and So Forth). An adversary can override variables leveraging user-supplied, untrusted query variables directly used on the application server without any data sanitization. In extreme cases, the adversary can change variables controlling the business logic of the application. For instance, in languages like PHP, a number of poorly set default configurations may allow the user to override variables.