CVE intelligence and bounded remediation
CVE-2021-39184 — Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS
Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. A vulnerability in versions prior to 11.5.0, 12.1.0, and 13.3.0 allows a sandboxed renderer to request a "thumbnail" image of an arbitrary file on the user's system. The thumbnail can potentially include significant parts of the original file, including textual data in many cases. Versions 15.0.0-alpha.10, 14.0.0, 13.3.0, 12.1.0, and 11.5.0 all contain a fix for the vulnerability. Two workarounds aside from upgrading are available. One may make the vulnerability significantly more difficult for an attacker to exploit by enabling `contextIsolation` in one's app. One may also disable the functionality of the `createThumbnailFromPath` API if one does not need it.
- Severity
- High
- CVSS
- 8.6 (3.1)
- Published
- 2021-10-12
- CISA KEV
- Not currently listed
- Ecosystem
- javascript/npm
- Weaknesses
- CWE-668, CWE-862
Affected products
- electronjs / electron
- electronjs / electron / 14.0.0
Matched remediation archetype
Authorization bypass, IDOR, and cross-tenant access
This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.
Check exposure
- Map object and action authorization checks across API, UI, batch, import/export, and background-job paths.
- Identify tenant, ownership, role, and policy boundaries for affected resources and administrative operations.
- Use synthetic fixtures to compare intended access matrices without accessing another user's real data.
Remediate safely
- Enforce server-side authorization at each resource access and state transition using the authenticated principal and trusted tenant context.
- Scope data queries by tenant and ownership; treat client-supplied identifiers, roles, and policy claims as untrusted.
- Add deny-by-default policy tests for horizontal and vertical access across every affected transport.
Authoritative sources
Complete CVE record and remediation plan
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