CVE-2026-34776

CVE-2026-34776 is a medium-severity vulnerability in Electronjs Electron with a CVSS 3.x base score of 5.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-125.

Key facts

Description

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.

Frequently asked questions

What is CVE-2026-34776?
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.
How severe is CVE-2026-34776?
CVE-2026-34776 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over local access with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability low.
Is CVE-2026-34776 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (12th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-34776?
CVE-2026-34776 primarily affects Electronjs Electron. In total, 15 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-34776?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-34776 have an EU (EUVD) identifier?
Yes. CVE-2026-34776 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-18951.
When was CVE-2026-34776 published?
CVE-2026-34776 was published on 2026-04-04 and last updated on 2026-06-17.

References

Affected products (15)

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