Prototype pollution via inherited __proto__ setter
Published Aug 5, 2026 · Updated Aug 5, 2026
Prototype pollution in affected Electron releases allows remote attackers to alter preload object behavior through contextBridge. CreateProxyForAPI copied an enumerable proto key with V8 Set, invoking the inherited Object.prototype.proto setter instead of creating an own property. Exposure requires preload code that accepts object arguments from untrusted content and reads inherited properties without own-property checks, enabling attacker-controlled data to influence privileged preload logic.
Summary
What happened
Prototype pollution in affected Electron releases allows remote attackers to alter preload object behavior through contextBridge. CreateProxyForAPI copied an enumerable proto key with V8 Set, invoking the inherited Object.prototype.proto setter instead of creating an own property. Exposure requires preload code that accepts object arguments from untrusted content and reads inherited properties without own-property checks, enabling attacker-controlled data to influence privileged preload logic.
The record
- CVE
- CVE-2026-70610
- Published
- Aug 5, 2026
- Updated
- Aug 5, 2026
- Vendor
- Electron
- Product
- Electron
- Classifications
- CWE-1321, T1203
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Aug 5, 2026CVE publishedPublication date reported by the CVE source.
- Aug 5, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=< 39.8.9
- Affected versionversion=>= 40.0.0-alpha.1, < 40.9.2
- Affected versionversion=>= 41.0.0-alpha.1, < 41.2.2
- Affected versionversion=>= 42.0.0-alpha.1, < 42.0.0-beta.4
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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