immutable-js up to 3.8.2/4.3.6/5.1.4 prototype pollution

CVSS Meta Temp Score
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CTI Interest Score
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5.1$0-$5k0.00

Summaryinfo

A vulnerability was found in immutable-js up to 3.8.2/4.3.6/5.1.4 and classified as problematic. This vulnerability affects the function mergeDeep/mergeDeepWith/merge/Map.toJS/Map.toObject. Executing a manipulation can lead to prototype pollution. This vulnerability appears as CVE-2026-29063. The attack may be performed from remote. There is no available exploit. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability has been found in immutable-js up to 3.8.2/4.3.6/5.1.4 and classified as problematic. This vulnerability affects the function mergeDeep/mergeDeepWith/merge/Map.toJS/Map.toObject. The manipulation with an unknown input leads to a prototype pollution vulnerability. The CWE definition for the vulnerability is 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. As an impact it is known to affect confidentiality. CVE summarizes:

Immutable.js provides many Persistent Immutable data structures. Prior to versions 3.8.3, 4.3.7, and 5.1.5, Prototype Pollution is possible in immutable via the mergeDeep(), mergeDeepWith(), merge(), Map.toJS(), and Map.toObject() APIs. This issue has been patched in versions 3.8.3, 4.3.7, and 5.1.5.

The advisory is shared for download at github.com. This vulnerability was named CVE-2026-29063 since 03/03/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. There are known technical details, but no exploit is available. The MITRE ATT&CK project declares the attack technique as T1059.

The vulnerability scanner Nessus provides a plugin with the ID 301405 (Linux Distros Unpatched Vulnerability : CVE-2026-29063), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 3.8.3, 4.3.7 or 5.1.5 eliminates this vulnerability. The upgrade is hosted for download at github.com.

The vulnerability is also documented in the databases at Tenable (301405) and CERT Bund (WID-SEC-2026-1007). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Affected

  • IBM App Connect Enterprise

Productinfo

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.1

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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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

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 301405
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2026-29063

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: immutable-js 3.8.3/4.3.7/5.1.5

Timelineinfo

03/03/2026 CVE reserved
03/06/2026 +3 days Advisory disclosed
03/06/2026 +0 days VulDB entry created
04/08/2026 +33 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: GHSA-wf6x-7x77-mvgw
Status: Confirmed

CVE: CVE-2026-29063 (🔒)
GCVE (CVE): GCVE-0-2026-29063
GCVE (VulDB): GCVE-100-349528
CERT Bund: WID-SEC-2026-1007 - IBM App Connect Enterprise: Mehrere Schwachstellen

Entryinfo

Created: 03/06/2026 21:19
Updated: 04/08/2026 15:37
Changes: 03/06/2026 21:19 (67), 03/07/2026 13:52 (2), 04/08/2026 15:37 (7)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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