{"cve":"CVE-2018-1000813","nvd":{"published":"2018-12-20T15:29:00.440","modified":"2026-06-17T01:33:06.020","status":"Modified","description":"Backdrop CMS version 1.11.0 and earlier contains a Cross Site Scripting (XSS) vulnerability in Sanitization of custom class names used on blocks and layouts. that can result in Execution of JavaScript from an unexpected source.. This attack appear to be exploitable via A user must be directed to an affected page while logged in.. This vulnerability appears to have been fixed in 1.11.1 and later.","cvss_v4":null,"cvss_v3":{"version":"3.0","vector":"CVSS:3.0/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N","score":4.8},"cwes":["CWE-79"],"references":["https://backdropcms.org/security/backdrop-sa-core-2018-005","https://backdropcms.org/security/backdrop-sa-core-2018-005"],"products":["backdropcms:backdrop_cms"],"source":"nvd","synced_at":"2026-10-19T20:54:36.112582389+00:00"},"epss":{"cve":"CVE-2018-1000813","score":0.00741,"percentile":0.54644,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}