{"id":"CVE-2026-14574","details":"In Eclipse Theia versions 0.7.0 and up until including 1.73.1, the `PreferenceUtils.merge` function in `@theia/core` recursively merges preference values without rejecting prototype-related keys (`__proto__`, `constructor`, `prototype`). Because this function is invoked by `PreferenceServiceImpl.doResolve` for every preference resolution across scopes (default, user, workspace, folder), a crafted preference value in a workspace settings file (`.theia/settings.json` or `.vscode/settings.json`) can pollute `Object.prototype` when the user opens the workspace, potentially altering application logic across the Theia process.","aliases":["GHSA-f3w9-qfw3-xr32"],"modified":"2026-08-12T03:51:13.318321622Z","published":"2026-08-05T10:51:47.869Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/14xxx/CVE-2026-14574.json","cna_assigner":"eclipse","cwe_ids":["CWE-1321"]},"references":[{"type":"WEB","url":"https://gitlab.eclipse.org/security/cve-assignment/-/work_items/157"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/14xxx/CVE-2026-14574.json"},{"type":"ADVISORY","url":"https://github.com/eclipse-theia/theia/security/advisories/GHSA-f3w9-qfw3-xr32"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-14574"},{"type":"REPORT","url":"https://gitlab.eclipse.org/security/vulnerability-reports/-/issues/567"},{"type":"EVIDENCE","url":"https://gitlab.eclipse.org/security/vulnerability-reports/-/work_items/567"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/eclipse-theia/theia","events":[{"introduced":"b67025d7165c8a3f0b7170efb044263992593813"},{"fixed":"172494ea2564ca07690e230805861146007fae79"}],"database_specific":{"source":["AFFECTED_FIELD","CPE_RANGE"],"cpe":"cpe:2.3:a:eclipse:theia:*:*:*:*:*:*:*:*","extracted_events":[{"introduced":"0.7.0"},{"fixed":"1.74.0"}]}}],"versions":["v1.73.0","v1.72.0","next","v1.71.0","v1.70.0","v1.69.0","v1.68.0","v1.67.0","v1.66.0","v1.65.0","v1.64.0","v1.63.0","v1.62.0","v1.61.0","v1.60.0","v1.59.0","v1.58.0","v1.57.0","v1.55.0","v1.56.0","v1.54.0","v1.53.0","v1.52.0","v1.50.0","v1.49.0","v1.48.0","v1.47.0","v1.46.0","v1.45.0","v1.44.0","v1.43.0","v1.42.0","v1.41.0","v1.40.0","v1.39.0","v1.38.0","v1.37.0","v1.36.0","v1.35.0","v1.34.0","v1.33.0","v1.32.0","v1.31.0","v1.30.0","v1.29.0","v1.28.0","v1.27.0","v1.26.0","v1.25.0","v1.24.0","v1.23.0","v1.22.1","v1.22.0","v1.21.0","v1.20.0","v1.17.0","v1.16.0","v1.15.0","v1.14.0","v1.13.0","1.13.0","v1.12.0","v1.11.0","v1.10.0","v1.9.0","v1.8.0","v1.7.0","v1.6.0","v1.5.0","v1.4.0","v1.3.0","v1.2.0","v1.1.0","v1.0.0","v0.16.0","v0.15.0","v0.14.0","v0.13.0","v0.12.0","v0.11.0","v0.10.0","v0.9.0","v0.8.0","v0.7.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-14574.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:A/VC:L/VI:H/VA:L/SC:N/SI:L/SA:L"}]}