Prototype Pollution in Electron
CVE-2026-70610
Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. Prior to 39.8.9, 40.9.2, 41.2.2, and 42.0.0-beta.4, objects copied across the contextBridge boundary from untrusted content could carry an attacker-influenced prototype, enabling prototype-pollution-style attacks against preload code despite context isolation being enabled. Apps are only affected if their preload code accepts object arguments from untrusted content and reads properties from them without own-property checks, while apps that only accept primitive arguments or validate object arguments are not affected. This issue is fixed in 39.8.9, 40.9.2, 41.2.2, and 42.0.0-beta.4.
Vulnerability class: Prototype Pollution
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N.
EPSS exploit prediction
EPSS: 0.006 (46.8th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 47th percentile — 46.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.006 · newest: 0.006 · change: -0.000
Affected products
- Electron — versions < 39.8.9, >= 40.0.0-alpha.1, < 40.9.2, >= 41.0.0-alpha.1, < 41.2.2
- Electronjs Electron — versions 42.0.0
Weakness classification (CWE)
References
- github.com/electron/electron/security/advisories/GHSA-ff2p-hmqr-hxm4 (Mitigation, Vendor Advisory)
- github.com/electron/electron/pull/51083 (Patch, Issue Tracking)
- github.com/electron/electron/pull/51084 (Patch, Issue Tracking)
- github.com/electron/electron/pull/51085 (Patch, Issue Tracking)
- github.com/electron/electron/pull/51086 (Patch, Issue Tracking)
- github.com/electron/electron/commit/17d5d26499cd279fab48f5f26527f8edc02a7713 (Patch)
- github.com/electron/electron/commit/23a6efb714dec80e2cf45d3054d18d701162e4dd (Patch)
- github.com/electron/electron/commit/4ac50292d552fb510eb778392620c85308770a55 (Patch)
- github.com/electron/electron/commit/5b699544cbbed51bedb7c60d75c8c42be5825737 (Patch)
- github.com/electron/electron/releases/tag/v39.8.9 (Release Notes)
Frequently asked questions
- What is CVE-2026-70610?
- CVE-2026-70610 is a medium-severity vulnerability in Electron, classified under Improperly Controlled Modification of Object Prototype Attributes (Prototype Pollution). CVSS score: 5.4/10. Published 2026-08-05.
- How severe is CVE-2026-70610?
- Medium severity. CVSS v3 base score is 5.4 out of 10.