CVE-2026-29063Public exploitNetwork attack vector

Object behavior manipulation via unsafe prototype-key assignment

Published Mar 6, 2026 · Updated Aug 26, 2026

Prototype pollution in Immutable.js before 3.8.3, 4.0.0-rc.1 through 4.3.7, and 5.0.0 through 5.1.4 allows attackers to alter returned objects. The merge APIs assign attacker-controlled keys to plain objects, while Map.toJS() and Map.toObject() copy keys without blocking proto. Reachability requires an application to pass untrusted keys into these APIs; pollution affects returned-object prototypes rather than global Object.prototype.

CVSS severity8.7
High
EPSS probability0.98%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Prototype pollution in Immutable.js before 3.8.3, 4.0.0-rc.1 through 4.3.7, and 5.0.0 through 5.1.4 allows attackers to alter returned objects. The merge APIs assign attacker-controlled keys to plain objects, while Map.toJS() and Map.toObject() copy keys without blocking proto. Reachability requires an application to pass untrusted keys into these APIs; pollution affects returned-object prototypes rather than global Object.prototype.

The record

CVE
CVE-2026-29063
Published
Mar 6, 2026
Updated
Aug 26, 2026
Vendor
389 Directory Server
Product
Red Hat Quay
Classifications
CWE-915, CWE-1321
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 6, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 26, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Affected versions are unavailable in this record. Check the vendor advisory for version and patch details.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

389 Directory Server · Red Hat QuayAffected versions are unavailable in this record.
389 Directory Server · Red Hat Quay 3.12Affected versions are unavailable in this record.
389 Directory Server · Red Hat OpenShift LightspeedAffected versions are unavailable in this record.
389 Directory Server · Red Hat OpenShift AIAffected versions are unavailable in this record.
389 Directory Server · Red Hat Edge ManagerAffected versions are unavailable in this record.
389 Directory Server · Red Hat OpenShift Pipelines 1.2Affected versions are unavailable in this record.
389 Directory Server · Red Hat Quay 3.1Affected versions are unavailable in this record.
389 Directory Server · Red Hat OpenShift Container Platform 4.16Affected versions are unavailable in this record.
389 Directory Server · Red Hat Developer HubAffected versions are unavailable in this record.
389 Directory Server · Red Hat build of Apicurio Registry 2Affected versions are unavailable in this record.
389 Directory Server · Red Hat OpenShift Data FoundationAffected versions are unavailable in this record.
389 Directory Server · multicluster engine for Kubernetes 2.6Affected versions are unavailable in this record.
389 Directory Server · Red Hat OpenShift Container Platform 4.21Affected versions are unavailable in this record.
389 Directory Server · Node Healthcheck OperatorAffected versions are unavailable in this record.
389 Directory Server · Red Hat Advanced Cluster Management for KubernetesAffected versions are unavailable in this record.
389 Directory Server · Red Hat Advanced Cluster Security for KubernetesAffected versions are unavailable in this record.
389 Directory Server · Red Hat OpenShift Container Platform 4.17Affected versions are unavailable in this record.
389 Directory Server · Red Hat OpenShift Container Platform 4.18Affected versions are unavailable in this record.
389 Directory Server · Red Hat OpenShift Data Foundation 4.18Affected versions are unavailable in this record.
389 Directory Server · multicluster engine for Kubernetes 2.10Affected versions are unavailable in this record.
389 Directory Server · Cluster Observability OperatorAffected versions are unavailable in this record.
389 Directory Server · Red Hat Ansible Automation PlatformAffected versions are unavailable in this record.
389 Directory Server · Red Hat Enterprise Linux 10Affected versions are unavailable in this record.
389 Directory Server · Red Hat OpenShift Container Platform 4.15Affected versions are unavailable in this record.
389 Directory Server · Red Hat OpenShift VirtualizationAffected versions are unavailable in this record.
389 Directory Server · Red Hat OpenShift Data Foundation 4.19Affected versions are unavailable in this record.
389 Directory Server · Red Hat OpenShift Container Platform 4.19Affected versions are unavailable in this record.
389 Directory Server · Red Hat OpenShift Service Mesh 3.1Affected versions are unavailable in this record.
389 Directory Server · Migration Toolkit for VirtualizationAffected versions are unavailable in this record.
389 Directory Server · Red Hat Connectivity LinkAffected versions are unavailable in this record.
389 Directory Server · Red Hat OpenShift Container Platform 4.13Affected versions are unavailable in this record.
389 Directory Server · Red Hat OpenShift GitOpsAffected versions are unavailable in this record.
389 Directory Server · Red Hat OpenShift Service Mesh 2.6Affected versions are unavailable in this record.
389 Directory Server · multicluster engine for Kubernetes 2.8Affected versions are unavailable in this record.
389 Directory Server · Network ObservabilityAffected versions are unavailable in this record.
389 Directory Server · Red Hat Migration ToolkitAffected versions are unavailable in this record.
389 Directory Server · Self-service automation portalAffected versions are unavailable in this record.
389 Directory Server · Red Hat 3scale API ManagementAffected versions are unavailable in this record.
389 Directory Server · Red Hat OpenShift Service Mesh 3.2Affected versions are unavailable in this record.
389 Directory Server · Red Hat OpenShift Service Mesh 3.3Affected versions are unavailable in this record.
389 Directory Server · Red Hat OpenShift Container Platform 4.12Affected versions are unavailable in this record.
389 Directory Server · Red Hat Quay 3.15Affected versions are unavailable in this record.
389 Directory Server · multicluster engine for Kubernetes 2.7Affected versions are unavailable in this record.
Immutable.js · Immutable.jsversion=< 3.8.3; version=< 4.3.7; version=< 5.1.5
389 Directory Server · Red Hat Discovery 2Affected versions are unavailable in this record.
389 Directory Server · Red Hat OpenShift Container Platform 4.14Affected versions are unavailable in this record.
389 Directory Server · Red Hat SatelliteAffected versions are unavailable in this record.
389 Directory Server · Red Hat Enterprise Linux 9Affected versions are unavailable in this record.
389 Directory Server · multicluster engine for Kubernetes 2.9Affected versions are unavailable in this record.
389 Directory Server · Red Hat OpenShift PipelinesAffected versions are unavailable in this record.
389 Directory Server · multicluster engine for KubernetesAffected versions are unavailable in this record.
389 Directory Server · Red Hat OpenShift Service Mesh 3Affected versions are unavailable in this record.
389 Directory Server · Logging Subsystem for Red Hat OpenShiftAffected versions are unavailable in this record.
389 Directory Server · Red Hat OpenShift Container Platform 4.20Affected versions are unavailable in this record.

Published CVSS scores

8.7GitHub CNACVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
8.8Red HatCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
9.8NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-915Improperly Controlled Modification of Dynamically-Determined Object Attributes
CWE-1321Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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