CVE-2026-2950
Prototype Pollution in Lodash _.unset and _.omit Functions
Publication date: 2026-03-31
Last updated on: 2026-04-07
Assigner: openjs
Description
Description
CVSS Scores
EPSS Scores
| Probability: | |
| Percentile: |
Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| lodash | lodash | From 4.0.0 (inc) to 4.17.23 (exc) |
| lodash | lodash-amd | From 4.0.0 (inc) to 4.17.23 (exc) |
| lodash | lodash-es | From 4.0.0 (inc) to 4.17.23 (exc) |
| lodash | lodash.unset | From 4.0.0 (inc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| 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. |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
Lodash versions 4.17.23 and earlier have a prototype pollution vulnerability in the _.unset and _.omit functions.
The fix for a related vulnerability only guards against string key members, but attackers can bypass this by using array-wrapped path segments.
This allows attackers to delete properties from built-in prototypes such as Object.prototype, Number.prototype, and String.prototype.
However, the vulnerability permits deletion of prototype properties but does not allow overwriting their original behavior.
How can this vulnerability impact me? :
An attacker exploiting this vulnerability can delete properties from built-in JavaScript prototypes.
This can lead to unexpected behavior or errors in applications relying on these prototypes.
The CVSS score of 6.5 indicates a medium severity with impact on integrity and availability.
There are no workarounds; upgrading to version 4.18.0 or later is required to fix the issue.
What immediate steps should I take to mitigate this vulnerability?
The immediate step to mitigate this vulnerability is to upgrade Lodash to version 4.18.0 or later, where the issue is patched.
There are no known workarounds other than upgrading to the patched version.