{"id":"CVE-2026-34774","aliases":["GHSA-532v-xpq5-8h95"],"url":"https://o3.security/vulnerability/CVE-2026-34774","summary":"Electron: Use-after-free in offscreen child window paint callback","details":"### Impact\nApps that use offscreen rendering and allow child windows via `window.open()` may be vulnerable to a use-after-free. If the parent offscreen `WebContents` is destroyed while a child window remains open, subsequent paint frames on the child dereference freed memory, which may lead to a crash or memory corruption.\n\nApps are only affected if they use offscreen rendering (`webPreferences.offscreen: true`) and their `setWindowOpenHandler` permits child windows. Apps that do not use offscreen rendering, or that deny child windows, are not affected.\n\n### Workarounds\nDeny child window creation from offscreen renderers in your `setWindowOpenHandler`, or ensure child windows are closed before the parent is destroyed.\n\n### Fixed Versions\n* `41.0.0`\n* `40.7.0`\n* `39.8.1`\n\n### For more information\nIf there are any questions or comments about this advisory, please email [security@electronjs.org](mailto:security@electronjs.org)","published":"2026-04-03T23:52:38.680Z","modified":"2026-08-12T16:23:49.557199Z","cvss":{"score":8.1,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"npm","name":"electron","fixedVersion":"39.8.1"},{"ecosystem":"npm","name":"electron","fixedVersion":"40.7.0"},{"ecosystem":"npm","name":"electron","fixedVersion":"41.0.0"}],"fix":null,"references":[{"type":"WEB","url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-34774.json"},{"type":"ADVISORY","url":"https://access.redhat.com/security/cve/CVE-2026-34774"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/34xxx/CVE-2026-34774.json"},{"type":"ADVISORY","url":"https://github.com/electron/electron/security/advisories/GHSA-532v-xpq5-8h95"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-34774"},{"type":"REPORT","url":"https://bugzilla.redhat.com/show_bug.cgi?id=2455026"},{"type":"PACKAGE","url":"https://github.com/electron/electron"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T16:23:49.557199Z"}}