Electron: contextBridge object copy honors prototype setters

Description

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.

Scores

EPSS (exploitation in 30 days)

0.56% · top 53% of all CVEs (6 Nov 2026)

CISA SSVC

Exploitation: none · Automatable: no · Technical impact: partial

The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.4.

Weakness

• CWE-1321: Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution') (opens in a new tab)All about CWE-1321 and its CVEs

Affected products

• electron · electron

  • affected < 39.8.9
  • affected >= 40.0.0-alpha.1, < 40.9.2
  • affected >= 41.0.0-alpha.1, < 41.2.2
  • affected >= 42.0.0-alpha.1, < 42.0.0-beta.4

Affected packages

From reviewed advisories of the GitHub Advisory Database.

• npmelectronGHSA-ff2p-hmqr-hxm4 (opens in a new tab)

References (13)

• https://github.com/electron/electron/security/advisories/GHSA-ff2p-hmqr-hxm4 (opens in a new tab)x_refsource_CONFIRM
• https://github.com/electron/electron/pull/51083 (opens in a new tab)x_refsource_MISC
• https://github.com/electron/electron/pull/51084 (opens in a new tab)x_refsource_MISC
• https://github.com/electron/electron/pull/51085 (opens in a new tab)x_refsource_MISC
• https://github.com/electron/electron/pull/51086 (opens in a new tab)x_refsource_MISC
• https://github.com/electron/electron/commit/17d5d26499cd279fab48f5f26527f8edc02a7713 (opens in a new tab)x_refsource_MISC
• https://github.com/electron/electron/commit/23a6efb714dec80e2cf45d3054d18d701162e4dd (opens in a new tab)x_refsource_MISC
• https://github.com/electron/electron/commit/4ac50292d552fb510eb778392620c85308770a55 (opens in a new tab)x_refsource_MISC
• https://github.com/electron/electron/commit/5b699544cbbed51bedb7c60d75c8c42be5825737 (opens in a new tab)x_refsource_MISC
• https://github.com/electron/electron/releases/tag/v39.8.9 (opens in a new tab)x_refsource_MISC
• https://github.com/electron/electron/releases/tag/v40.9.2 (opens in a new tab)x_refsource_MISC
• https://github.com/electron/electron/releases/tag/v41.2.2 (opens in a new tab)x_refsource_MISC
• https://github.com/electron/electron/releases/tag/v42.0.0-beta.4 (opens in a new tab)x_refsource_MISC

Sources

The same CVE in the primary databases and aggregators, to check against.

• CVE.org record (opens in a new tab)
• CVE List JSON (GitHub) (opens in a new tab)
• NVD (opens in a new tab)
• FIRST EPSS (opens in a new tab)
• OSV.dev (opens in a new tab)
• GitHub Advisory GHSA-ff2p-hmqr-hxm4 (opens in a new tab)
• CIRCL Vulnerability-Lookup (opens in a new tab)

Badge for a README or a ticket

[![CVE-2026-70610](https://trackcve.app/badge/CVE-2026-70610.svg)](https://trackcve.app/cve/CVE-2026-70610)

Record last updated 6 Aug 2026, 14:31 UTC.