{"id":"GHSA-5vf7-q87h-pg6w","summary":"Cross-Site Scripting in BookStack","details":"### Impact\n\nA user with permission to create comments could POST HTML directly to the system to be saved in a comment, which would then be executed/displayed to others users viewing the comment. Through this vulnerability custom JavaScript code could be injected and therefore ran on other user machines.\n\nThis most impacts scenarios where not-trusted users are given permission to create comments.\n\n### Patches\n\nThe issue was addressed in BookStack v0.29.2.\n\nAfter upgrading, The command `php artisan bookstack:regenerate-comment-content` should be ran to remove any pre-existing dangerous content. \n\n### Workarounds\n\nComments can be disabled in the system settings to prevent them being shown to users. Alternatively, comment creation permissions can be altered as required to only those who are trusted but this will not address existing exploitation of this vulnerability. \n\n### References\n\n* [BookStack Beta v0.29.2](https://github.com/BookStackApp/BookStack/releases/tag/v0.29.2)\n* JVN#41035278\n* [BookStack Blog Post](https://bookstackapp.com/blog/beta-release-v0-29-2/)\n\n### For more information\n\nIf you have any questions or comments about this advisory:\n* Open an issue in [the BookStack GitHub repository](BookStackApp/BookStack/issues).\n* Ask on the [BookStack Discord chat](https://discord.gg/ztkBqR2).\n* Follow the [BookStack Security Advice](https://github.com/BookStackApp/BookStack#-security) to contact someone privately.","aliases":["CVE-2020-11055"],"modified":"2026-09-10T03:48:45.764750308Z","published":"2020-05-07T21:10:26Z","database_specific":{"cwe_ids":["CWE-79"],"severity":"MODERATE","github_reviewed":true,"github_reviewed_at":"2020-05-07T18:36:46Z","nvd_published_at":null},"references":[{"type":"WEB","url":"https://github.com/BookStackApp/BookStack/security/advisories/GHSA-5vf7-q87h-pg6w"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2020-11055"},{"type":"WEB","url":"https://bookstackapp.com/blog/beta-release-v0-29-2"},{"type":"WEB","url":"https://github.com/BookStackApp/BookStack/releases/tag/v0.29.2"},{"type":"WEB","url":"http://jvn.jp/en/jp/JVN41035278/index.html"}],"affected":[{"package":{"name":"ssddanbrown/bookstack","ecosystem":"Packagist","purl":"pkg:composer/ssddanbrown/bookstack"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0.18.0"},{"fixed":"0.29.2"}]}],"versions":["v0.18.0","v0.18.1","v0.18.2","v0.18.3","v0.18.4","v0.18.5","v0.19.0","v0.20.0","v0.20.1","v0.20.2","v0.20.3","v0.21.0","v0.22.0","v0.23.0","v0.23.1","v0.23.2","v0.24.0","v0.24.1","v0.24.2","v0.24.3","v0.25.0","v0.25.1","v0.25.2","v0.25.3","v0.25.4","v0.25.5","v0.26.0","v0.26.1","v0.26.2","v0.26.3","v0.26.4","v0.27","v0.27.1","v0.27.2","v0.27.3","v0.27.4","v0.27.5","v0.28.0","v0.28.1","v0.28.2","v0.28.3","v0.29.0","v0.29.1"],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2020/05/GHSA-5vf7-q87h-pg6w/GHSA-5vf7-q87h-pg6w.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L"}]}