{"cve":"CVE-2021-3313","nvd":{"published":"2021-05-20T16:15:08.283","modified":"2026-06-17T04:04:55.457","status":"Modified","description":"Plone CMS until version 5.2.4 has a stored Cross-Site Scripting (XSS) vulnerability in the user fullname property and the file upload functionality. The user's input data is not properly encoded when being echoed back to the user. This data can be interpreted as executable code by the browser and allows an attacker to execute JavaScript in the context of the victim's browser if the victim opens a vulnerable page containing an XSS payload.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N","score":5.4},"cwes":["CWE-79"],"references":["http://www.openwall.com/lists/oss-security/2021/05/22/1","https://plone.org/download/releases/5.2.3","https://plone.org/security/hotfix/20210518","https://www.compass-security.com/fileadmin/Research/Advisories/2021-07_CSNC-2021-013_XSS_in_Plone_CMS.txt","http://www.openwall.com/lists/oss-security/2021/05/22/1"],"products":["plone:plone"],"source":"nvd","synced_at":"2026-10-19T21:18:09.669877188+00:00"},"epss":{"cve":"CVE-2021-3313","score":0.00978,"percentile":0.62186,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-hprr-4vfq-fcxw","url":"https://osv.dev/vulnerability/GHSA-hprr-4vfq-fcxw","summary":"Plone XSS in User Fullname Property and File Upload","modified":"2024-10-15T17:23:10.518204Z","packages":[{"ecosystem":"PyPI","name":"plone","purl":"pkg:pypi/plone","ranges":["<5.2.4"],"fixed":["5.2.4"]}]},{"id":"PYSEC-2021-78","url":"https://osv.dev/vulnerability/PYSEC-2021-78","summary":"","modified":"2026-06-10T17:01:38.058787506Z","packages":[{"ecosystem":"PyPI","name":"plone","purl":"pkg:pypi/plone","ranges":["<5.2.4"],"fixed":["5.2.4"]}]}],"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."]}