{"id":"CVE-2026-23891","aliases":["GHSA-fc46-r95f-hq7g"],"url":"https://o3.security/vulnerability/CVE-2026-23891","summary":"Decidim has a Cross-site scripting (XSS) vulnerability via user name field","details":"### Impact\nA stored code execution vulnerability in the user name field allows a low-privileged attacker to execute arbitrary code in the context of any user who passively visits a comment page, resulting in high confidentiality and integrity impact across security boundaries.\n\n### Patches\nN/A\n\n### Workarounds\nNot available\n\n### References\nOWASP ASVS v4.0.3-5.1.3\n\n### Credits\nThis issue was discovered in a security audit organized by [octree](https://octree.ch/) and made by [Secu Labs](https://seculabs.ch/) against Decidim financed by the city of Lausanne (Switzerland).","published":"2026-04-13T16:52:16.448Z","modified":"2026-08-12T03:51:14.034818637Z","cvss":null,"epss":{"score":0.00356,"percentile":0.29234,"asOf":"2026-09-17"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"RubyGems","name":"decidim-core","fixedVersion":"0.31.1"},{"ecosystem":"RubyGems","name":"decidim-core","fixedVersion":"0.30.5"}],"fix":null,"references":[{"type":"WEB","url":"https://github.com/decidim/decidim/releases/tag/v0.30.5"},{"type":"WEB","url":"https://github.com/decidim/decidim/releases/tag/v0.31.1"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/23xxx/CVE-2026-23891.json"},{"type":"ADVISORY","url":"https://github.com/decidim/decidim/security/advisories/GHSA-fc46-r95f-hq7g"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-23891"},{"type":"PACKAGE","url":"https://github.com/decidim/decidim"},{"type":"WEB","url":"https://github.com/rubysec/ruby-advisory-db/blob/master/gems/decidim-core/CVE-2026-23891.yml"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:14.034818637Z"}}