{"id":"CVE-2026-21872","state":"PUBLISHED","title":"NiceGUI apps are vulnerable to XSS which uses `ui.sub_pages` and render arbitrary user-provided links","description":"NiceGUI is a Python-based UI framework. From versions 2.22.0 to 3.4.1, an unsafe implementation in the click event listener used by ui.sub_pages, combined with attacker-controlled link rendering on the page, causes XSS when the user actively clicks on the link. This issue has been patched in version 3.5.0.","publishedAt":"2026-01-08T09:50:02.801Z","updatedAt":"2026-01-08T15:13:11.652Z","severity":{"score":6.1,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","source":"GitHub_M"},"assigner":"GitHub_M","products":["zauberzeug nicegui"],"affected":[{"vendor":"zauberzeug","product":"nicegui","versions":[{"version":">= 2.22.0, < 3.5.0","status":"affected"}]}],"references":["https://github.com/zauberzeug/nicegui/security/advisories/GHSA-m7j5-rq9j-6jj9","https://github.com/zauberzeug/nicegui/releases/tag/v3.5.0"],"weaknesses":["CWE-79"],"ingestedAt":"2026-10-29T20:11:10.572Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/21xxx/CVE-2026-21872.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-21872","state":"PUBLISHED","datePublished":"2026-01-08T09:50:02.801Z","dateUpdated":"2026-01-08T15:13:11.652Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-01-05T16:44:16.369Z"},"containers":{"cna":{"title":"NiceGUI apps are vulnerable to XSS which uses `ui.sub_pages` and render arbitrary user-provided links","descriptions":[{"lang":"en","value":"NiceGUI is a Python-based UI framework. From versions 2.22.0 to 3.4.1, an unsafe implementation in the click event listener used by ui.sub_pages, combined with attacker-controlled link rendering on the page, causes XSS when the user actively clicks on the link. This issue has been patched in version 3.5.0."}],"affected":[{"vendor":"zauberzeug","product":"nicegui","versions":[{"version":">= 2.22.0, < 3.5.0","status":"affected"}]}],"references":[{"url":"https://github.com/zauberzeug/nicegui/security/advisories/GHSA-m7j5-rq9j-6jj9","name":"https://github.com/zauberzeug/nicegui/security/advisories/GHSA-m7j5-rq9j-6jj9","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/zauberzeug/nicegui/releases/tag/v3.5.0","name":"https://github.com/zauberzeug/nicegui/releases/tag/v3.5.0","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":6.1,"baseSeverity":"MEDIUM","confidentialityImpact":"LOW","integrityImpact":"LOW","privilegesRequired":"NONE","scope":"CHANGED","userInteraction":"REQUIRED","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-79","lang":"en","description":"CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-01-08T09:50:02.801Z"},"source":{"advisory":"GHSA-m7j5-rq9j-6jj9","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-01-08T15:12:53.988468Z","id":"CVE-2026-21872","options":[{"Exploitation":"poc"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-01-08T15:13:11.652Z"}}]}}}