CVE Intelligence
High Injection

CVE-2026-114125 — Storybook: Missing origin validation in Storybook preview allows code injection from malicious websites

Storybook is a frontend workshop for building user interface components and pages in isolation. From 8.0.0 until 8.6.19, 9.1.21, 10.6.2, and 11.0.0-alpha.6, a malicious website can interact with the preview of a running Storybook development server. Insufficient iframe embedding and message-origin restrictions can allow attacker-controlled events to reach the running preview. A developer must visit the malicious website and interact with the injected interface. The attack can cause unauthorized changes to story files and, if a changed file is later executed by a local runtime, arbitrary code execution with the developer's privileges. This issue is fixed in 8.6.19, 9.1.21, 10.6.2, and 11.0.0-alpha.6.

Published Oct 21, 2026 · Updated Oct 22, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP, GitHub Security Advisories · CNA: GitHub_M

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.
How the score was calculated
  • EPSS 0.4% (30-day exploitation probability)+5
  • Technical severity (high)+6

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation
Not confirmed
Not in CISA KEV — an absence of record, not proof it is unexploited.
EPSS FIRST
0.38%
ahead of 30% of scored CVEs · Oct 24, 2026
Affects
Storybookjs
Storybook and 5 more
CVSS base
8.6
High · 2 source(s)

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

  • Npm Storybook: fixed in version 8.6.19 — github.com (GitHub Security Advisories)
  • Npm Storybook: fixed in version 9.1.21 — github.com (GitHub Security Advisories)
  • Npm Storybook: fixed in version 10.6.2 — github.com (GitHub Security Advisories)
  • Npm Storybook: fixed in version 11.0.0-alpha.6 — github.com (GitHub Security Advisories)
  • Npm @storybook/core: fixed in version 8.6.19 — github.com (GitHub Security Advisories)
  • Npm @storybook/core-server: fixed in version 8.6.19 — github.com (GitHub Security Advisories)
  • Npm @storybook/experimental-addon-test: fixed in version 8.6.19 — github.com (GitHub Security Advisories)
  • Npm @storybook/addon-vitest: fixed in version 9.1.21 — github.com (GitHub Security Advisories)
  • Npm @storybook/addon-vitest: fixed in version 10.6.2 — github.com (GitHub Security Advisories)
  • Npm @storybook/addon-vitest: fixed in version 11.0.0-alpha.6 — github.com (GitHub Security Advisories)
  • Npm @storybook/addon-mcp: fixed in version 10.6.2 — github.com (GitHub Security Advisories)
  • Npm @storybook/addon-mcp: fixed in version 11.0.0-alpha.6 — github.com (GitHub Security Advisories)

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

  1. Identify exposed assets running the affected vendor/product/version combinations (Storybookjs Storybook, Npm @storybook/addon-mcp, Npm @storybook/addon-vitest…).
  2. The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
  3. Apply the fixed version or the patch documented under Remediation.
  4. Exploitation requires user interaction: tighten email/web filtering and warn affected users.
  5. Search available logs for exploit probes matching the vulnerability class (injection), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

VendorProductVersionsStatusSource
Storybookjs Storybook version >= 8.0.0, < 8.6.19version >= 9.0.0, < 9.1.21version >= 10.0.0, < 10.6.2version >= 11.0.0-alpha.0, < 11.0.0-alpha.6 Vulnerable CVE Program (cve.org) e CISA ADP
Npm @storybook/addon-mcp ≥ 10.6.0 and < 10.6.2≥ 11.0.0-alpha.0 and < 11.0.0-alpha.6 Vulnerable GitHub Security Advisories
Npm @storybook/addon-vitest ≥ 9.0.0 and < 9.1.21≥ 10.0.0 and < 10.6.2≥ 11.0.0-alpha.0 and < 11.0.0-alpha.6 Vulnerable GitHub Security Advisories
Npm @storybook/core ≥ 8.0.0 and < 8.6.19 Vulnerable GitHub Security Advisories
Npm @storybook/core-server ≥ 8.0.0 and < 8.6.19 Vulnerable GitHub Security Advisories
Npm @storybook/experimental-addon-test ≥ 8.0.0 and < 8.6.19 Vulnerable GitHub Security Advisories
Npm Storybook ≥ 8.0.0 and < 8.6.19≥ 9.0.0 and < 9.1.21≥ 10.0.0 and < 10.6.2≥ 11.0.0-alpha.0 and < 11.0.0-alpha.6 Vulnerable GitHub Security Advisories

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector
Network
Attack complexity
Low
Attack requirements
None
Privileges required
None
User interaction
Active
Scope
X
Confidentiality (vulnerable system)
High
Integrity (vulnerable system)
High
Availability (vulnerable system)
High
Confidentiality (subsequent)
None
Integrity (subsequent)
None
Availability (subsequent)
None

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

ScoreVersionSeverityExpl.ImpactScored by
8.6 CVSS 4.0 High — — security-advisories@github.com via NIST National Vulnerability Database
8.6 CVSS 4.0 High — — GitHub_M via CVE Program (cve.org) e CISA ADP
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X (score shown at the top: security-advisories@github.com)

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-94 · Code Injection

Other CVEs with this weakness →

EPSS over time FIRST

Oct 22, 2026 → Oct 24, 2026 · 3 reading(s) · max 0.38%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

  • Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
  • Look for parameters with command/query metacharacters and unexpected child processes of the service.
web/proxy/WAF logsnetwork IDS/IPSapplication logsendpoint telemetry (EDR)

Timeline

What happened to this CVE, newest first.

  • 2026
  • Source status changed · Received → Awaiting Analysis
    Oct 22, 2026 · NIST National Vulnerability Database
  • Fix documented
    Oct 21, 2026 · GitHub Security Advisories
  • Affected products added · npm/storybook, npm/@storybook/core, npm/@storybook/core-server, npm/@storybook/experimental-addon-test, npm/@storybook/a
    Oct 21, 2026 · GitHub Security Advisories
  • Affected products added · storybookjs/storybook
    Oct 21, 2026 · CVE Program (cve.org) e CISA ADP
  • Record published
    Oct 21, 2026
  • CVSS changed · 8.6
    Oct 21, 2026 · NIST National Vulnerability Database
  • Source status changed · → Received
    Oct 21, 2026 · NIST National Vulnerability Database
  • Record created in this database
    Oct 21, 2026 · Alertas do Telegram
  • CVE published
    Oct 21, 2026 · GitHub_M

Source activity

Repeated readings are counted rather than listed.

  • 2× References added · Oct 21, 2026 – Oct 21, 2026
  • 1× Official description updated · Oct 21, 2026 – Oct 21, 2026

References

13 on the record

Elsewhere on this site

Storybookjs
every CVE for this vendor
Injection
same class
CWE-94
other pages naming this weakness

Related CVEs (same products)

  • CVE-2026-114126 Storybook dev server: devices on the same network can obtain the WebSocket token and write code into story files 3d
  • CVE-2026-27148 Storybook Dev Server Vulnerable to WebSocket Hijacking Feb 25, 2026
  • CVE-2025-68429 Storybook manager bundle may expose environment variables during build Dec 17, 2025

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

  • No CISA SSVC assessment.
  • No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
  • No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
  • No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-114125 is "Storybook: Missing origin validation in Storybook preview allows code injection from malicious websites", rated High. It affects Storybook (Storybookjs); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 8.6 describes technical severity. EPSS 0.38% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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