{"id":"CVE-2026-31860","state":"PUBLISHED","title":"Unhead has a XSS bypass in `useHeadSafe` via attribute name injection and case-sensitive protocol check","description":"Unhead is a document head and template manager. Prior to 2.1.11, useHeadSafe() can be bypassed to inject arbitrary HTML attributes, including event handlers, into SSR-rendered <head> tags. This is the composable that Nuxt docs recommend for safely handling user-generated content. The acceptDataAttrs function (safe.ts, line 16-20) allows any property key starting with data- through to the final HTML. It only checks the prefix, not whether the key contains spaces or other characters that break HTML attribute parsing. This vulnerability is fixed in 2.1.11.","publishedAt":"2026-03-12T17:18:20.452Z","updatedAt":"2026-03-13T16:26:51.670Z","severity":{"score":5.3,"label":"Medium","version":"4.0","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N","source":"GitHub_M"},"assigner":"GitHub_M","products":["unjs unhead"],"affected":[{"vendor":"unjs","product":"unhead","versions":[{"version":"< 2.1.11","status":"affected"}]}],"references":["https://github.com/unjs/unhead/security/advisories/GHSA-g5xx-pwrp-g3fv"],"weaknesses":["CWE-79"],"ingestedAt":"2026-10-29T20:11:40.391Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/31xxx/CVE-2026-31860.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-31860","state":"PUBLISHED","datePublished":"2026-03-12T17:18:20.452Z","dateUpdated":"2026-03-13T16:26:51.670Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-03-09T19:02:25.012Z"},"containers":{"cna":{"title":"Unhead has a XSS bypass in `useHeadSafe` via attribute name injection and case-sensitive protocol check","descriptions":[{"lang":"en","value":"Unhead is a document head and template manager. Prior to 2.1.11, useHeadSafe() can be bypassed to inject arbitrary HTML attributes, including event handlers, into SSR-rendered <head> tags. This is the composable that Nuxt docs recommend for safely handling user-generated content. The acceptDataAttrs function (safe.ts, line 16-20) allows any property key starting with data- through to the final HTML. It only checks the prefix, not whether the key contains spaces or other characters that break HTML attribute parsing. This vulnerability is fixed in 2.1.11."}],"affected":[{"vendor":"unjs","product":"unhead","versions":[{"version":"< 2.1.11","status":"affected"}]}],"references":[{"url":"https://github.com/unjs/unhead/security/advisories/GHSA-g5xx-pwrp-g3fv","name":"https://github.com/unjs/unhead/security/advisories/GHSA-g5xx-pwrp-g3fv","tags":["x_refsource_CONFIRM"]}],"metrics":[{"cvssV4_0":{"attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"NONE","userInteraction":"PASSIVE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE","vulnAvailabilityImpact":"NONE","subConfidentialityImpact":"LOW","subIntegrityImpact":"LOW","subAvailabilityImpact":"NONE","baseScore":5.3,"baseSeverity":"MEDIUM","vectorString":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N","version":"4.0"}}],"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":"2026-03-12T17:18:20.452Z"},"source":{"advisory":"GHSA-g5xx-pwrp-g3fv","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/unjs/unhead/security/advisories/GHSA-g5xx-pwrp-g3fv","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-03-13T16:26:47.686961Z","id":"CVE-2026-31860","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":"2026-03-13T16:26:51.670Z"}}]}}}