{"id":"CVE-2026-23891","aliases":["EUVD-2026-22024","GHSA-fc46-r95f-hq7g"],"status":"published","title":"Decidim has a Cross-site scripting (XSS) vulnerability via user name field","description":"Decidim is a participatory democracy framework. In versions below 0.30.5 and 0.31.0.rc1 through 0.31.0, a 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. This issue has been fixed in versions 0.30.5 and 0.31.1.","severity":{"version":"4.0","score":9.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:H/VI:H/VA:L/SC:H/SI:H/SA:L","level":"critical","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-12","score":0.0037,"percentile":0.31359,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-79"],"published":"2026-04-13T16:35:13Z","modified":"2026-10-28T02:31:13Z","fixes":[{"ecosystem":"RubyGems","package":"decidim-core","fixed_in":["0.31.0","0.30.5","0.31.1"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"RubyGems","package":"decidim-core","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0.31.0.rc1"},{"fixed":"0.31.0"}]}]},{"source":"ghsa","ecosystem":"RubyGems","package":"decidim-core","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.30.5"}]}]},{"source":"osv","ecosystem":"RubyGems","package":"decidim-core","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0.31.0.rc1"},{"fixed":"0.31.1"}]}],"versions":["0.31.0","0.31.0.rc1","0.31.0.rc2"]},{"source":"osv","ecosystem":"RubyGems","package":"decidim-core","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.30.5"}]}],"versions":["0.0.1","0.0.1.alpha1","0.0.1.alpha2","0.0.1.alpha3","0.0.1.alpha4","0.0.1.alpha5","0.0.1.alpha6","0.0.1.alpha7","0.0.1.alpha8","0.0.1.alpha9","0.0.2","0.0.3","0.0.5","0.0.6","0.0.7","0.0.8.1","0.1.0","0.10.0","0.10.1","0.11.0.pre1","0.11.1","0.11.2","0.12.0","0.12.0.pre","0.12.1","0.12.2","0.13.0","0.13.0.pre1","0.13.1","0.14.1","0.14.2","0.14.3","0.14.4","0.15.0","0.15.1","0.15.2","0.16.0","0.16.1","0.17.0","0.17.1","0.17.2","0.18.0","0.18.1","0.19.0","0.19.1","0.2.0","0.20.0","0.20.1","0.21.0","0.22.0","0.23.0","0.23.1","0.23.1.rc1","0.23.2","0.23.3","0.23.4","0.23.5","0.23.6","0.24.0","0.24.0.rc1","0.24.0.rc2","0.24.1","0.24.2","0.24.3","0.25.0","0.25.0.rc1","0.25.0.rc2","0.25.0.rc3","0.25.0.rc4","0.25.1","0.25.2","0.26.0","0.26.0.rc1","0.26.0.rc2","0.26.1","0.26.10","0.26.2","0.26.3","0.26.4","0.26.5","0.26.7","0.26.8","0.26.9","0.27.0","0.27.0.rc1","0.27.0.rc2","0.27.1","0.27.10","0.27.2","0.27.3","0.27.4","0.27.5","0.27.6","0.27.7","0.27.8","0.27.9","0.28.0","0.28.0.rc4","0.28.0.rc5","0.28.1","0.28.2","0.28.3","0.28.4","0.28.5","0.28.6","0.29.0","0.29.0.rc1","0.29.0.rc2","0.29.0.rc3","0.29.0.rc4","0.29.1","0.29.2","0.29.3","0.29.4","0.29.5","0.29.6","0.29.7","0.3.0","0.3.1","0.3.2","0.30.0","0.30.0.rc1","0.30.0.rc2","0.30.0.rc3","0.30.1","0.30.2","0.30.3","0.30.4","0.4.0","0.4.1","0.4.2","0.4.3","0.4.4","0.5.0","0.5.1","0.6.0","0.6.1","0.6.2","0.6.3","0.6.4","0.6.5","0.6.6","0.6.7","0.6.8","0.7.0","0.7.1","0.7.2","0.7.3","0.7.4","0.8.0","0.8.1","0.8.2","0.8.3","0.8.4","0.9.0","0.9.1","0.9.2","0.9.3"]}],"products":[{"vendor":"decidim","product":"decidim"}],"references":[{"url":"https://github.com/decidim/decidim/security/advisories/GHSA-fc46-r95f-hq7g","tags":["x_refsource_CONFIRM","Vendor Advisory","advisory","web"]},{"url":"https://github.com/decidim/decidim/releases/tag/v0.30.5","tags":["x_refsource_MISC","Product","Release Notes","web"]},{"url":"https://github.com/decidim/decidim/releases/tag/v0.31.1","tags":["x_refsource_MISC","Product","Release Notes","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-23891","tags":["advisory"]},{"url":"https://github.com/rubysec/ruby-advisory-db/blob/master/gems/decidim-core/CVE-2026-23891.yml","tags":["web"]},{"url":"https://github.com/advisories/GHSA-fc46-r95f-hq7g"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/23xxx/CVE-2026-23891.json","tags":["advisory"]},{"url":"https://github.com/decidim/decidim","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2026-23891","title":"Decidim has a Cross-site scripting (XSS) vulnerability via user name field","description":"Decidim is a participatory democracy framework. In versions below 0.30.5 and 0.31.0.rc1 through 0.31.0, a 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. This issue has been fixed in versions 0.30.5 and 0.31.1.","status":"published","published":"2026-04-13T16:52:16.448Z","modified":"2026-04-14T16:29:24.311Z","cvss":[{"version":"4.0","score":9.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:H/VI:H/VA:L/SC:H/SI:H/SA:L","level":"critical","assessor":"cna"}],"cwes":["CWE-79"],"updated_at":"2026-11-02T13:42:04.39372Z"}],"euvd":[{"id":"EUVD-2026-22024","description":"Decidim is a participatory democracy framework. In versions below 0.30.5 and 0.31.0.rc1 through 0.31.0, a 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. This issue has been fixed in versions 0.30.5 and 0.31.1.","status":"published","published":"2026-04-13T16:52:16Z","modified":"2026-04-14T16:29:24Z","cvss":[{"version":"4.0","score":9.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:H/VI:H/VA:L/SC:H/SI:H/SA:L","level":"critical"}],"updated_at":"2026-11-02T19:24:25.999353Z"}],"ghsa":[{"id":"GHSA-fc46-r95f-hq7g","title":"Decidim has a cross-site scripting (XSS) in user name","description":"### 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).","status":"published","published":"2026-04-13T16:35:13Z","modified":"2026-05-13T16:14:14Z","cvss":[{"version":"4.0","score":9.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:H/VI:H/VA:L/SC:H/SI:H/SA:L","level":"critical"},{"version":"3.1","score":8.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N","level":"high"}],"cwes":["CWE-79"],"updated_at":"2026-11-02T14:40:08.003212Z"}],"nvd":[{"id":"CVE-2026-23891","description":"Decidim is a participatory democracy framework. In versions below 0.30.5 and 0.31.0.rc1 through 0.31.0, a 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. This issue has been fixed in versions 0.30.5 and 0.31.1.","status":"published","published":"2026-04-13T17:16:28.063Z","modified":"2026-06-17T10:22:16.033Z","cvss":[{"version":"4.0","score":9.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:H/VI:H/VA:L/SC:H/SI:H/SA:L/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":"critical","assessor":"secondary"},{"version":"3.1","score":8.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N","level":"high","assessor":"primary"}],"cwes":["CWE-79"],"updated_at":"2026-11-02T14:12:14.37744Z"}],"osv":[{"id":"CVE-2026-23891","title":"Decidim has a Cross-site scripting (XSS) vulnerability via user name field","description":"Decidim is a participatory democracy framework. In versions below 0.30.5 and 0.31.0.rc1 through 0.31.0, a 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. This issue has been fixed in versions 0.30.5 and 0.31.1.","status":"published","published":"2026-04-13T16:52:16.448Z","modified":"2026-10-28T02:31:13.542071085Z","cvss":[{"version":"4.0","score":9.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:H/VI:H/VA:L/SC:H/SI:H/SA:L","level":"critical"}],"cwes":["CWE-79"],"updated_at":"2026-11-02T15:44:59.079784Z"},{"id":"GHSA-fc46-r95f-hq7g","title":"Decidim has a cross-site scripting (XSS) in user name","description":"### 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).","status":"published","published":"2026-04-13T16:35:13Z","modified":"2026-05-13T16:38:42.323225Z","cvss":[{"version":"3.1","score":8.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N","level":"high"},{"version":"4.0","score":9.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:H/VI:H/VA:L/SC:H/SI:H/SA:L","level":"critical"}],"cwes":["CWE-79"],"updated_at":"2026-11-02T15:46:46.39441Z"}]}}