Bug 2455021 (CVE-2026-34776)

Summary: CVE-2026-34776 Electron: Electron: Information disclosure via crafted second-instance message
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
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Priority: medium    
Version: unspecifiedKeywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in Electron, a framework for building desktop applications. On macOS and Linux, a local user could exploit an out-of-bounds heap read vulnerability by sending a specially crafted message to an Electron application that uses the `app.requestSingleInstanceLock()` function. Apps that do not call app.requestSingleInstanceLock() are not affected. This could lead to the disclosure of sensitive memory contents, potentially revealing confidential information. This issue affects only processes running under the same user as the Electron application.
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Bug Depends On: 2455446, 2455447    
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Description OSIDB Bzimport 2026-04-04 01:01:18 UTC 
Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. Prior to versions 38.8.6, 39.8.1, 40.8.1, and 41.0.0, on macOS and Linux, apps that call app.requestSingleInstanceLock() were vulnerable to an out-of-bounds heap read when parsing a crafted second-instance message. Leaked memory could be delivered to the app's second-instance event handler. This issue is limited to processes running as the same user as the Electron app. Apps that do not call app.requestSingleInstanceLock() are not affected. Windows is not affected by this issue. This issue has been patched in versions 38.8.6, 39.8.1, 40.8.1, and 41.0.0.