VDB-385115 · CVE-2026-54737 · GCVE-0-2026-54737

phun-ky defaults-deep up to 2.0.4 defaultsDeep prototype pollution

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
6.0	$0-$5k	1.16+

Summaryinfo

A vulnerability has been found in phun-ky defaults-deep up to 2.0.4 and classified as critical. Impacted is the function defaultsDeep. The manipulation leads to prototype pollution. This vulnerability is referenced as CVE-2026-54737. Remote exploitation of the attack is possible. No exploit is available.

Detailsinfo

A vulnerability was found in phun-ky defaults-deep up to 2.0.4 and classified as critical. This issue affects the function defaultsDeep. The manipulation with an unknown input leads to a prototype pollution vulnerability. Using CWE to declare the problem leads to 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. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

@phun-ky/defaults-deep is a library like lodash defaultsDeep with array preservation and no lodash dependency. Prior to 2.0.5, defaultsDeep() recursively merges user-supplied objects without filtering proto, constructor, and prototype, allowing properties to be written to Object.prototype. This issue is fixed in version 2.0.5.

It is possible to read the advisory at github.com. The identification of this vulnerability is CVE-2026-54737 since 06/16/2026. The exploitation is known to be easy. The attack may be initiated remotely. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1059 according to MITRE ATT&CK.

Upgrading to version 2.0.5 eliminates this vulnerability.

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Vendor

phun-ky

Name

defaults-deep

Version

Website

Product: https://github.com/phun-ky/defaults-deep/

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.0

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Prototype pollution
CWE: CWE-1321 / CWE-94 / CWE-74
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: defaults-deep 2.0.5

Timelineinfo

06/16/2026 CVE reserved
07/31/2026 +45 days Advisory disclosed
07/31/2026 +0 days VulDB entry created
07/31/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-54737 (🔒)
GCVE (CVE): GCVE-0-2026-54737
GCVE (VulDB): GCVE-100-385115

Entryinfo

Created: 07/31/2026 20:20
Changes: 07/31/2026 20:20 (55)
Complete: 🔍
Cache ID: 216::103