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Fencer Vulns
high 7.5

CVE-2026-46625 json

JavaScript Cookie: Per-instance prototype hijack in assign() enables cookie-attribute injection

published 2026-05-21 5 mo ago modified 2026-09-10 1 mo ago also GHSA-qjx8-664m-686j , EUVD-2026-36154

cvss
7.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.9%
EPSS 0.9% chance of exploitation in 30 days, percentile 60%
public exploits
0
none known

Summary

JavaScript Cookie is a JavaScript API for handling cookies, client-side. Prior to version 3.0.7, js-cookie's internal assign() helper copies properties with for...in + plain assignment. When the source object is produced by JSON.parse, the JSON object's "__proto__" member is an own enumerable property, so the for…in enumerates it and the target[key] = source[key] write triggers the Object.prototype.__proto__ setter on the fresh target ({}). The result is a per-instance prototype hijack: Object.prototype itself is untouched, but the merged attributes object now inherits attacker-controlled keys. Because the consuming set() function then enumerates the merged object with another for...in, every key the attacker placed on the polluted prototype lands in the resulting Set-Cookie string as an attribute pair. The attacker can set domain=, secure=, samesite=, expires=, and path= on cookies whose attributes the developer thought were locked down. This issue has been patched in version 3.0.7.

Patch / fix

  • npm js-cookie 3.0.7
  • Red Hat Cryostat 4 on RHEL 9 4.2.0-13
  • Red Hat Red Hat Advanced Cluster Security for Kubernetes 4.10 1783357140
  • Red Hat Red Hat Ansible Automation Platform 2.1 1787047114
  • Red Hat Red Hat Ansible Automation Platform 2.2 1787047188
  • Red Hat Red Hat Ansible Automation Platform 2.7 1787218409
  • Red Hat Red Hat Developer Hub 1.10 1785332928, 1785333413, 1785340831, 1785411652
  • Red Hat Red Hat Developer Hub 1.9 1785972843
  • Red Hat Red Hat OpenShift AI 3.4 1786611759, 1786612219, 1787250508, 1787250617, 1787251250, 1787251550, 1787347991
  • Red Hat Red Hat OpenShift Service Mesh 3.3 1782201466, 1782231869
  • node-js-cookie Debian 14 3.0.7+~3.0.6-1

debian advisories DEBIAN-CVE-2026-46625

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-46625 updated cvss 7.5

js-cookie: JavaScript Cookie: Cookie attribute manipulation via prototype pollution

  • Red Hat OpenShift Lightspeed openshift-lightspeed/lightspeed-console-plugin-rhel9, openshift-lightspeed/lightspeed-console-plugin-419-rhel9 Red Hat 3scale API Management Platform 2 3scale-amp2/system-rhel9
    affected: workaround, no fix available
  • Red Hat Ansible Automation Platform 2 automation-hub, python-galaxy-ng, automation-gateway, python3x-galaxy-ng, python3.11-galaxy-ng, automation-platform-ui, +1 more
    affected: workaround, no fix available, no fix planned “Will not fix”
  • Red Hat JBoss Enterprise Application Platform 7 js-cookie
    affected: workaround, no fix planned “Will not fix”
  • Red Hat OpenShift Container Platform 5 openshift5/ose-agent-installer-ui-rhel9
    affected: workaround, no fix available
  • Red Hat Cryostat 4 on RHEL 9 cryostat/cryostat-grafana-dashboard-rhel9 4.2.0-13
    fixed: vendor fix RHSA-2026:48151
  • Red Hat Advanced Cluster Security for Kubernetes for IBM Power, little endian 4.10 advanced-cluster-security/rhacs-main-rhel8 1783357140
    fixed: vendor fix RHSA-2026:36625
  • Red Hat Ansible Automation Platform 2.1 ansible-automation-platform/automation-portal 1787047114
    fixed: vendor fix RHSA-2026:56338
  • Red Hat Ansible Automation Platform 2.2 ansible-automation-platform/automation-portal 1787047188
    fixed: vendor fix RHSA-2026:56357
show 10 more
  • Red Hat Ansible Automation Platform 2.7 ansible-automation-platform-27/gateway-rhel9 1787218409
    fixed: vendor fix RHSA-2026:59153
  • Red Hat Developer Hub 1.9 rhdh/rhdh-hub-rhel9 1785972843
    fixed: vendor fix RHSA-2026:52768
  • Red Hat Developer Hub 1.10 rhdh/rhdh-hub-rhel9 1785411652, rhdh/red-hat-developer-hub-backstage-plugin-lightspeed 1785333413, rhdh/red-hat-developer-hub-backstage-plugin-orchestrator 1785340831, rhdh/red-hat-developer-hub-backstage-plugin-orchestrator-form-widgets 1785332928
    fixed: vendor fix RHSA-2026:48126
  • Red Hat OpenShift AI 3.4 rhoai/odh-dashboard-rhel9 1787347991, rhoai/odh-mod-arch-maas-rhel9 1787251250, rhoai/odh-mod-arch-automl-rhel9 1787250508, rhoai/odh-mod-arch-gen-ai-rhel9 1786611759, rhoai/odh-mod-arch-mlflow-rhel9 1786612219, rhoai/odh-mod-arch-autorag-rhel9 1787251550, +2 more
    fixed: vendor fix RHSA-2026:60520
  • Red Hat OpenShift Service Mesh 3.3 openshift-service-mesh/kiali-rhel9 1782201466, openshift-service-mesh/kiali-ossmc-rhel9 1782231869
    fixed: vendor fix RHSA-2026:33183
  • Red Hat Cryostat 4 on RHEL 9 cryostat/cryostat-rhel9 4.2.0-13, cryostat/cryostat-db-rhel9 4.2.0-19, cryostat/jfr-datasource-rhel9 4.2.0-13, cryostat/cryostat-reports-rhel9 4.2.0-13, cryostat/cryostat-storage-rhel9 4.2.0-19, cryostat/cryostat-rhel9-operator 4.2.0-18, +3 more
    not affected: vulnerable code not present
  • Red Hat 3scale API Management Platform 2 3scale-amp21/system, 3scale-amp22/system, 3scale-amp2/system-rhel7, 3scale-amp2/system-rhel8
    not affected: component not present
  • Red Hat Advanced Cluster Security for Kubernetes for IBM Power, little endian 4.10 advanced-cluster-security/rhacs-fact-rhel8 1782356145, advanced-cluster-security/rhacs-roxctl-rhel8 1783357140, advanced-cluster-security/rhacs-scanner-rhel8 1782891789, advanced-cluster-security/rhacs-rhel8-operator 1783357140, advanced-cluster-security/rhacs-collector-rhel8 1782187369, advanced-cluster-security/rhacs-operator-bundle 1783357140, +6 more Red Hat Ansible Automation Platform 2 python3.12-galaxy-ng Red Hat Ansible Automation Platform 2.7 ansible-automation-platform-27/hub-rhel9 1787223293, ansible-automation-platform-27/hub-web-rhel9 1787225966, ansible-automation-platform-27/receptor-rhel9 1787216969, ansible-automation-platform-27/mcp-tools-rhel9 1787218205, ansible-automation-platform-27/controller-rhel9 1787220257, ansible-automation-platform-27/de-minimal-rhel9 1787224014, +25 more Red Hat Developer Hub 1.9 rhdh/rhdh-rhel9-operator 1785972533, rhdh/rhdh-operator-bundle 1785976147 Red Hat Developer Hub 1.10 rhdh/rhdh-rhel9-operator 1785411290, rhdh/rhdh-operator-bundle 1785415596, rhdh/rhdh-must-gather-rhel9 1784202439, rhdh/rhdh-rag-content-rhel9 1785162496, rhdh/red-hat-developer-hub-backstage-plugin-lightspeed-backend 1785332487, rhdh/red-hat-developer-hub-backstage-plugin-orchestrator-backend 1785332825, +2 more Red Hat Discovery 2 discovery/discovery-ui-rhel9
    +3 more products
    Red Hat Enterprise Linux 8 grafana, grafana-pcp, grafana-loki, grafana-mssql, grafana-mysql, grafana-selinux, +9 more Red Hat Enterprise Linux 9 grafana-pcp Red Hat Enterprise Linux 10 grafana-pcp
    not affected: vulnerable code not present
  • Red Hat JBoss Enterprise Application Platform 8 js-cookie Red Hat JBoss Enterprise Application Platform Expansion Pack js-cookie
    not affected: inline mitigations already exist
  • Red Hat OpenShift AI 3.4 rhoai/odh-cli-rhel9 1787330837, rhoai/odh-cli-rhel9 1791509689, rhoai/rhai-cli-rhel9 1787330837, rhoai/rhai-cli-rhel9 1791509689, rhoai/odh-automl-rhel9 1786612415, rhoai/odh-automl-rhel9 1791535789, +198 more Red Hat OpenShift Container Platform 4 openshift4/ose-agent-installer-ui-rhel9 Red Hat OpenShift Service Mesh 3.3 openshift-service-mesh/kiali-rhel9-operator 1782231576, openshift-service-mesh/kiali-operator-bundle 1782295602
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
Proof of concept is public
Automatable
yes
Technical impact
partial
Assessed
4 mo ago

Exploit prediction

0.92% chance of exploitation in the next 30 days, higher than 60% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • github.com https://github.com/js-cookie/js-cookie/security/advisories/GHSA-qjx8-664m-686j referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
CISA ADP 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
GitHub 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Affected packages

ecosystem package affected fixed in
npm js-cookie
<3.0.7
3.0.7

Affected products

  • js-cookie js-cookie
  • Red Hat Cryostat 4 on RHEL 9
  • Red Hat Red Hat Advanced Cluster Security for Kubernetes 4.10
  • Red Hat Red Hat Ansible Automation Platform 2.1
  • Red Hat Red Hat Ansible Automation Platform 2.2
  • Red Hat Red Hat Ansible Automation Platform 2.7
  • Red Hat Red Hat Developer Hub 1.10
  • Red Hat Red Hat Developer Hub 1.9
  • Red Hat Red Hat OpenShift AI 3.4
  • Red Hat Red Hat OpenShift Service Mesh 3.3
  • Red Hat OpenShift Lightspeed
  • Red Hat Red Hat 3scale API Management Platform 2
  • Red Hat Red Hat Ansible Automation Platform 2
  • Red Hat Red Hat Discovery 2
  • Red Hat Red Hat Enterprise Linux 10
  • Red Hat Red Hat Enterprise Linux 8
  • Red Hat Red Hat Enterprise Linux 9
  • Red Hat Red Hat JBoss Enterprise Application Platform 7
  • Red Hat Red Hat JBoss Enterprise Application Platform 8
  • Red Hat Red Hat JBoss Enterprise Application Platform Expansion Pack
  • Red Hat Red Hat OpenShift AI (RHOAI)
  • Red Hat Red Hat OpenShift Container Platform 4

Classification

Weakness
  • CWE-1321 Improperly Controlled Modification of Object Prototype Attributes
  • CWE-915 Improperly Controlled Modification of Dynamically-Determined Object Attributes

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.