{"cve":"CVE-2026-21873","nvd":{"published":"2026-01-08T10:15:55.617","modified":"2026-06-17T10:19:04.083","status":"Analyzed","description":"NiceGUI is a Python-based UI framework. From versions 2.22.0 to 3.4.1, an unsafe implementation in the pushstate event listener used by ui.sub_pages allows an attacker to manipulate the fragment identifier of the URL, which they can do despite being cross-site, using an iframe. This issue has been patched in version 3.5.0.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","score":6.1},"cwes":["CWE-79"],"references":["https://github.com/zauberzeug/nicegui/releases/tag/v3.5.0","https://github.com/zauberzeug/nicegui/security/advisories/GHSA-mhpg-c27v-6mxr"],"products":["zauberzeug:nicegui"],"source":"nvd","synced_at":"2026-10-19T22:19:41.481987139+00:00"},"epss":{"cve":"CVE-2026-21873","score":0.0026,"percentile":0.17784,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-mhpg-c27v-6mxr","url":"https://osv.dev/vulnerability/GHSA-mhpg-c27v-6mxr","summary":"NiceGUI apps which use `ui.sub_pages` vulnerable to zero-click XSS","modified":"2026-07-07T17:57:37.927767983Z","packages":[{"ecosystem":"PyPI","name":"nicegui","purl":"pkg:pypi/nicegui","ranges":[">=2.22.0 <3.5.0"],"fixed":["3.5.0"]}]},{"id":"PYSEC-2026-1702","url":"https://osv.dev/vulnerability/PYSEC-2026-1702","summary":"NiceGUI apps which use `ui.sub_pages` vulnerable to zero-click XSS","modified":"2026-07-07T17:46:58.610773531Z","packages":[{"ecosystem":"PyPI","name":"nicegui","purl":"pkg:pypi/nicegui","ranges":[">=2.22.0 <3.5.0"],"fixed":["3.5.0"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}