CVE-2026-70610: Electron · contextBridge object copy honors prototype setters
Affects electronSource GCVE Database
Not known to be exploited · CVSS 5.4 Medium : upgrade to 39.8.9 when convenient.
Data as of 3 Nov 2026, 22:58 UTC
- EPSS
- 0.5% chance of exploitation in 30 days – higher than 46% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 39.8.9, 40.9.2, 41.2.2 +1
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:NExploitation evidence
Disclosed: evidence found.
CVE published 5 Aug 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 3 Nov 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| npmelectron | Affected
| Fixed in
|
| npmelectron | Affected
| Fixed in
|
| npmelectron | Affected
| Fixed in
|
| npmelectron | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A fix is available in Electron versions 39.8.9 and later. Users should upgrade to one of these fixed versions. As a workaround, preload code should validate objects received from untrusted content using own-property checks (e.g., Object.hasOwn) or copy objects onto null-prototype objects before use to prevent prototype pollution.
Description
A vulnerability in Electron's contextBridge allows objects copied from untrusted content to carry attacker-influenced prototypes, enabling prototype-pollution-style attacks against preload code despite context isolation. This affects apps that accept object arguments from untrusted content and read their properties without own-property checks. The issue is fixed in Electron versions 39.8.9 and later.
References
- github.com/electron/electron/security/advisories/GHSA-ff2p-hmqr-hxm4 (opens in a new tab)
- github.com/electron/electron/pull/51083 (opens in a new tab)
- github.com/electron/electron/pull/51084 (opens in a new tab)
- github.com/electron/electron/pull/51085 (opens in a new tab)
- github.com/electron/electron/pull/51086 (opens in a new tab)
- github.com/electron/electron/commit/17d5d26499cd279fab48f5f26527f8edc02a7713 (opens in a new tab)
- github.com/electron/electron/commit/23a6efb714dec80e2cf45d3054d18d701162e4dd (opens in a new tab)
- github.com/electron/electron/commit/4ac50292d552fb510eb778392620c85308770a55 (opens in a new tab)
- github.com/electron/electron/commit/5b699544cbbed51bedb7c60d75c8c42be5825737 (opens in a new tab)
- github.com/electron/electron (opens in a new tab)
- github.com/electron/electron/releases/tag/v39.8.9 (opens in a new tab)
- github.com/electron/electron/releases/tag/v40.9.2 (opens in a new tab)
- github.com/electron/electron/releases/tag/v41.2.2 (opens in a new tab)
- github.com/electron/electron/releases/tag/v42.0.0-beta.4 (opens in a new tab)