{"affected":[{"defaultStatus":"unaffected","ecosystem":"github","packageName":"AppFlowy-IO/AppFlowy-Cloud","product":"AppFlowy-Cloud","source":"CNA: VulnCheck","vendor":"AppFlowy-IO","versions":[{"lessThanOrEqual":"0.9.64","status":"affected","version":"0","versionType":"semver"}]}],"cveId":"CVE-2026-127203","cwes":["CWE-79"],"description":"AppFlowy Cloud through 0.9.64 contains a stored cross-site scripting vulnerability that allows authenticated workspace members to upload blobs with unvalidated Content-Type values that are later served inline without a Content-Disposition header or authentication on the retrieval route. Attackers can upload a text/html or image/svg+xml blob via put_blob_handler, which is then rendered as an active same-origin document through the unauthenticated get_blob_handler endpoint and cached immutably for one year, enabling persistent script execution against any visitor who accesses the URL.","epss":null,"exploits":[{"kind":"exploit","source":"CNA: VulnCheck","url":"https://gist.github.com/mtholmquist/9b9683104fc3b5d78a488c06a6674e5c"}],"kev":null,"metrics":[{"score":5.1,"severity":"medium","source":"CNA: VulnCheck","vector":"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"},{"score":5.4,"severity":"medium","source":"CNA: VulnCheck","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N","version":"3.1"},{"score":5.1,"severity":"medium","source":"NVD: disclosure@vulncheck.com","vector":"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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","version":"4.0"},{"score":5.4,"severity":"medium","source":"NVD: disclosure@vulncheck.com","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N","version":"3.1"}],"modifiedAt":1794503863653,"publishedAt":1794501760069,"references":[{"source":"CNA: VulnCheck","tags":["technical-description","exploit"],"url":"https://gist.github.com/mtholmquist/9b9683104fc3b5d78a488c06a6674e5c"},{"source":"CNA: VulnCheck","tags":["third-party-advisory"],"url":"https://www.vulncheck.com/advisories/appflowy-cloud-stored-xss-via-blob-upload-content-type"},{"source":"disclosure@vulncheck.com","tags":[],"url":"https://gist.github.com/mtholmquist/9b9683104fc3b5d78a488c06a6674e5c"},{"source":"disclosure@vulncheck.com","tags":[],"url":"https://www.vulncheck.com/advisories/appflowy-cloud-stored-xss-via-blob-upload-content-type"}],"remediation":[],"revision":"ae57b7e5160233f4c9a6a2e2577f5cf80695d09790fe1e49745c1e3ef17e55aa","sources":[{"modifiedAt":1794501760069,"name":"CNA: VulnCheck","retrievedAt":1794503452465,"url":"https://www.cve.org/CVERecord?id=CVE-2026-127203"},{"modifiedAt":1794503863653,"name":"NVD","retrievedAt":1794507525064,"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-127203"}],"ssvc":null,"status":"published","title":"AppFlowy Cloud 0.9.64 Stored XSS via Blob Upload Content-Type","updatedAt":1794507525064}