{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-85600","assignerOrgId":"83251b91-4cc7-4094-a5c7-464a1b83ea10","state":"PUBLISHED","assignerShortName":"VulnCheck","dateReserved":"2026-09-04T11:00:28.731Z","datePublished":"2026-09-04T11:30:02.813Z","dateUpdated":"2026-09-05T10:28:17.769Z"},"containers":{"cna":{"providerMetadata":{"orgId":"83251b91-4cc7-4094-a5c7-464a1b83ea10","shortName":"VulnCheck","dateUpdated":"2026-09-05T10:28:17.769Z"},"datePublic":"2026-08-20T00:00:00.000Z","title":"Grav Admin before 2.0.21 Stored XSS via username","descriptions":[{"lang":"en","value":"Grav Admin (getgrav/grav-plugin-admin2) versions <= 2.0.19 contain a stored cross-site scripting vulnerability in the tHtml() function (src/lib/stores/i18n.svelte.ts), which substitutes untrusted parameters such as usernames into translation templates before parsing the result as markdown. Grav's server-side username validation (DataUser::isValidUsername) blocks filesystem-dangerous characters but not <, >, \", or ', allowing an attacker to register a username containing an HTML payload. When an administrator views a UI surface that renders the username through tHtml()—such as the two-factor force-disable confirmation prompt or the 'page is locked' editor notice—the payload executes in their authenticated session. Fixed in 2.0.21."}],"problemTypes":[{"descriptions":[{"lang":"en","description":"Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')","cweId":"CWE-79","type":"CWE"}]}],"affected":[{"vendor":"getgrav","product":"grav-plugin-admin2","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","versionType":"semver","lessThanOrEqual":"2.0.19"},{"version":"2.0.21","status":"unaffected","versionType":"semver"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:a:getgrav:grav:*:*:*:*:*:*:*:*","versionEndExcluding":"2.0.21"}]}]}],"metrics":[{"cvssV4_0":{"Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","Safety":"NOT_DEFINED","attackComplexity":"LOW","attackRequirements":"NONE","attackVector":"NETWORK","baseScore":5.1,"baseSeverity":"MEDIUM","exploitMaturity":"NOT_DEFINED","privilegesRequired":"LOW","providerUrgency":"NOT_DEFINED","subAvailabilityImpact":"NONE","subConfidentialityImpact":"LOW","subIntegrityImpact":"LOW","userInteraction":"PASSIVE","valueDensity":"NOT_DEFINED","vectorString":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N","version":"4.0","vulnAvailabilityImpact":"NONE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE","vulnerabilityResponseEffort":"NOT_DEFINED"},"format":"CVSS"},{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":5.4,"baseSeverity":"MEDIUM","confidentialityImpact":"LOW","integrityImpact":"LOW","privilegesRequired":"LOW","scope":"CHANGED","userInteraction":"REQUIRED","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N","version":"3.1"},"format":"CVSS"}],"references":[{"url":"https://github.com/getgrav/grav/security/advisories/GHSA-96xm-c5hr-59rx","tags":["vendor-advisory"],"name":"GitHub Security Advisory (GHSA-96xm-c5hr-59rx)"},{"name":"VulnCheck Advisory: Grav Admin before 2.0.21 Stored XSS via username","tags":["third-party-advisory"],"url":"https://www.vulncheck.com/advisories/grav-admin-before-2.0.21-stored-xss-via-username"}],"credits":[{"lang":"en","value":"alham-rizvi","type":"reporter"}],"x_generator":{"engine":"vulncheck-endgame"}},"adp":[{"references":[{"url":"https://github.com/getgrav/grav/security/advisories/GHSA-96xm-c5hr-59rx","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-09-04T13:53:08.429568Z","id":"CVE-2026-85600","options":[{"Exploitation":"poc"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2026-09-04T13:54:30.112Z"}}]}}