{"id":"CVE-2026-126498","aliases":["EUVD-2026-123063","GHSA-43p2-x762-x6h7","GHSA-cwxm-8ch5-j2vh"],"status":"published","title":"WriteFreely before 0.17.3 Stored XSS via Unsanitized Post Slug","description":"WriteFreely before 0.17.3 contains a stored cross-site scripting vulnerability that allows authenticated authors to inject HTML by supplying a malicious post slug via the CreatePost API. The raw slug is concatenated into an anchor by augmentReadingDestination() for paid-shortcode posts, executing script for RSS/Atom feed readers, newsletter recipients and ActivityPub viewers.","severity":{"version":"4.0","score":5.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.00232,"percentile":0.1424,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-79"],"published":"2026-11-11T00:58:50Z","modified":"2026-11-11T10:47:27Z","products":[{"vendor":"musing studio","product":"writefreely"}],"references":[{"url":"https://github.com/writefreely/writefreely/security/advisories/GHSA-cwxm-8ch5-j2vh","tags":["vendor-advisory","advisory"]},{"url":"https://github.com/writefreely/writefreely/commit/d7231d81a914f1314a218d5e8fde6e0341391ccd","tags":["patch","fix"]},{"url":"https://github.com/writefreely/writefreely/releases/tag/v0.17.3","tags":["release-notes","advisory"]},{"url":"https://github.com/writefreely/writefreely/blob/v0.17.2/postrender.go#L117-L121","tags":["technical-description","article"]},{"url":"https://github.com/writefreely/writefreely/blob/v0.17.2/database.go#L702-L705","tags":["technical-description","article"]},{"url":"https://www.vulncheck.com/advisories/writefreely-before-0.17.3-stored-xss-via-unsanitized-post-slug","tags":["third-party-advisory","advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-126498","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-43p2-x762-x6h7"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/126xxx/CVE-2026-126498.json","tags":["advisory"]},{"url":"https://github.com/writefreely/writefreely","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2026-126498","title":"WriteFreely before 0.17.3 Stored XSS via Unsanitized Post Slug","description":"WriteFreely before 0.17.3 contains a stored cross-site scripting vulnerability that allows authenticated authors to inject HTML by supplying a malicious post slug via the CreatePost API. The raw slug is concatenated into an anchor by augmentReadingDestination() for paid-shortcode posts, executing script for RSS/Atom feed readers, newsletter recipients and ActivityPub viewers.","status":"published","published":"2026-11-11T00:58:50.974Z","modified":"2026-11-11T00:58:50.974Z","cvss":[{"version":"4.0","score":5.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N","level":"medium","assessor":"cna"},{"version":"3.1","score":5.4,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N","level":"medium","assessor":"cna"}],"cwes":["CWE-79"],"updated_at":"2026-11-11T01:51:22.146863Z"}],"euvd":[{"id":"EUVD-2026-123063","description":"WriteFreely before 0.17.3 contains a stored cross-site scripting vulnerability that allows authenticated authors to inject HTML by supplying a malicious post slug via the CreatePost API. The raw slug is concatenated into an anchor by augmentReadingDestination() for paid-shortcode posts, executing script for RSS/Atom feed readers, newsletter recipients and ActivityPub viewers.","status":"published","published":"2026-11-11T00:58:50Z","modified":"2026-11-11T00:58:50Z","cvss":[{"version":"4.0","score":5.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N","level":"medium"}],"updated_at":"2026-11-11T06:27:36.75899Z"}],"ghsa":[{"id":"GHSA-43p2-x762-x6h7","title":"WriteFreely before 0.17.3 contains a stored cross-site scripting vulnerability that allows...","description":"WriteFreely before 0.17.3 contains a stored cross-site scripting vulnerability that allows authenticated authors to inject HTML by supplying a malicious post slug via the CreatePost API. The raw slug is concatenated into an anchor by augmentReadingDestination() for paid-shortcode posts, executing script for RSS/Atom feed readers, newsletter recipients and ActivityPub viewers.","status":"published","published":"2026-11-11T03:34:26Z","modified":"2026-11-11T03:34:27Z","cvss":[{"version":"4.0","score":5.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/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","level":"medium"},{"version":"3.1","score":5.4,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N","level":"medium"}],"cwes":["CWE-79"],"updated_at":"2026-11-11T04:01:27.974473Z"}],"nvd":[{"id":"CVE-2026-126498","description":"WriteFreely before 0.17.3 contains a stored cross-site scripting vulnerability that allows authenticated authors to inject HTML by supplying a malicious post slug via the CreatePost API. The raw slug is concatenated into an anchor by augmentReadingDestination() for paid-shortcode posts, executing script for RSS/Atom feed readers, newsletter recipients and ActivityPub viewers.","status":"published","published":"2026-11-11T01:17:14.79Z","modified":"2026-11-11T01:17:14.79Z","cvss":[{"version":"4.0","score":5.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/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","level":"medium","assessor":"secondary"},{"version":"3.1","score":5.4,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N","level":"medium","assessor":"primary"}],"cwes":["CWE-79"],"updated_at":"2026-11-11T07:23:51.781546Z"}],"osv":[{"id":"CVE-2026-126498","title":"WriteFreely before 0.17.3 Stored XSS via Unsanitized Post Slug","description":"WriteFreely before 0.17.3 contains a stored cross-site scripting vulnerability that allows authenticated authors to inject HTML by supplying a malicious post slug via the CreatePost API. The raw slug is concatenated into an anchor by augmentReadingDestination() for paid-shortcode posts, executing script for RSS/Atom feed readers, newsletter recipients and ActivityPub viewers.","status":"published","published":"2026-11-11T00:58:50.974Z","modified":"2026-11-12T02:48:36.088256733Z","cvss":[{"version":"4.0","score":5.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N","level":"medium"}],"cwes":["CWE-79"],"updated_at":"2026-11-12T03:30:48.739835Z"}]}}