{"cve":"CVE-2021-3163","nvd":{"published":"2021-04-12T21:15:14.340","modified":"2026-06-17T04:04:46.467","status":"Modified","description":"A vulnerability in the HTML editor of Slab Quill 4.8.0 allows an attacker to execute arbitrary JavaScript by storing an XSS payload (a crafted onloadstart attribute of an IMG element) in a text field. Note: Researchers have claimed that this issue is not within the product itself, but is intended behavior in a web browser","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","score":6.1},"cwes":["CWE-79"],"references":["https://burninatorsec.blogspot.com/2021/04/cve-2021-3163-xss-slab-quill-js.html","https://github.com/quilljs/quill/issues/3273","https://github.com/quilljs/quill/issues/3364","https://quilljs.com","https://burninatorsec.blogspot.com/2021/04/cve-2021-3163-xss-slab-quill-js.html"],"products":["slab:quill"],"source":"nvd","synced_at":"2026-10-19T21:17:01.373894544+00:00"},"epss":{"cve":"CVE-2021-3163","score":0.01311,"percentile":0.70658,"date":"2026-11-01"},"kev":null,"osv":[{"id":"GHSA-4943-9vgg-gr5r","url":"https://osv.dev/vulnerability/GHSA-4943-9vgg-gr5r","summary":"Cross-site Scripting in quill","modified":"2024-08-09T14:41:50Z","packages":[{"ecosystem":"npm","name":"quill","purl":"pkg:npm/quill","ranges":["<=1.3.7"],"fixed":[]}]}],"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."]}