CVE-2026-114126
From 8.0.0 until 8.6.19, 9.1.21, 10.6.2, and 11.0.0-alpha.6, the Storybook development server can expose its WebSocket authentication token to clients able to load its HTML pages over a local network.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.53%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
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, the Storybook development server can expose its WebSocket authentication token to clients able to load its HTML pages over a local network. A LAN attacker can obtain the token and invoke WebSocket-backed file-writing or testing functionality. Weak story-write validation can allow code to be placed in story files. If the Storybook Vitest addon is installed with an old version of Vitest, the payload can use a Vitest API to write additional files or execute commands. Depending on the payload and local tooling, the attack can lead to 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.
- CVSS 4.0
- 8.7 HIGHCVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- 0.53% probability · 44th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-22, CWE-94, CWE-306
- Source
- security-advisories@github.com
EPSS moved from 0.5% on 22 October 2026 to 0.5% on 26 October 2026.
References
- https://github.com/storybookjs/storybook/commit/243c06bf8f1e2f09446c44868ea100261e1374da
- https://github.com/storybookjs/storybook/commit/3be03ec6f11f4616471cebc3fc65c13e1bf8c178
- https://github.com/storybookjs/storybook/commit/5540f03b209cc56c66f56a9c7cb4b2ee5b883ce5
- https://github.com/storybookjs/storybook/commit/a9ef9345d73224c73e0b81dc2701ec5b465ea9bb
- https://github.com/storybookjs/storybook/commit/d9b09e332510a88689c71ecc081bbbc2d072476e
- https://github.com/storybookjs/storybook/commit/df3fed468c9b4830605f00068c4bc6b7e1e215ed
- https://github.com/storybookjs/storybook/pull/36726
- https://github.com/storybookjs/storybook/releases/tag/v10.6.2
- https://github.com/storybookjs/storybook/releases/tag/v11.0.0-alpha.6
- https://github.com/storybookjs/storybook/releases/tag/v8.6.19
- https://github.com/storybookjs/storybook/releases/tag/v9.1.21
- https://github.com/storybookjs/storybook/security/advisories/GHSA-px85-f4q5-jh77
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.