{"items":[{"id":"NVI-00005770","kind":"vulnerability","title":"XSS in Flarum Sticky extension","revision":2,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected.","NVD lastModified does not establish freshness of every associated CPE record."],"lifecycle":"active","identifiers":["GHSA-h3gg-7wx2-cq3h","CVE-2021-21283"],"plain_summary":"OSV carries this publisher advisory for flarum/sticky. This is an aggregated source copy; consult the original publisher and compare update dates.","review_status":"source_listed","control_topics":[],"public_actions":[{"summary":"The original advisory lists fixed boundaries 0.1.0-beta.15.1 for flarum/sticky. Confirm the publisher’s latest guidance.","source_ids":["sr-9bfacdceb041be3a8e068b90185c5892"],"action_type":"vendor_patch","limitations":"Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system.","current_supported_target":null},{"summary":"Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.","source_ids":["sr-51f7af318a1b691324ca83ee68751368"],"action_type":"investigate","limitations":"Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system.","current_supported_target":null}],"schema_version":"1.1.0","source_metrics":[{"kind":"CVSS","as_of":"2026-06-17T03:35:11.463Z","value":"3.5 LOW (2.0)","meaning":"nvd@nist.gov severity; no combined Null risk score.","source_id":"sr-51f7af318a1b691324ca83ee68751368"},{"kind":"CVSS","as_of":"2026-06-17T03:35:11.463Z","value":"5.4 MEDIUM (3.1)","meaning":"security-advisories@github.com severity; no combined Null risk score.","source_id":"sr-51f7af318a1b691324ca83ee68751368"},{"kind":"CVSS","as_of":"2026-06-17T03:35:11.463Z","value":"5.4 MEDIUM (3.1)","meaning":"nvd@nist.gov severity; no combined Null risk score.","source_id":"sr-51f7af318a1b691324ca83ee68751368"}],"why_it_matters":"Published affected context helps an owner decide what evidence to gather. This report has not examined your application.","related_sources":[{"id":"sr-9bfacdceb041be3a8e068b90185c5892","url":"https://github.com/advisories/GHSA-h3gg-7wx2-cq3h","basis":"vendor_advisory","notes":"GitHub-origin advisory, CC-BY-4.0; OSV is an aggregate copy, not independent corroboration.","title":"GHSA-h3gg-7wx2-cq3h","publisher":"GitHub Advisory Database via OSV","observed_at":"2026-10-31T21:42:20.424Z"},{"id":"sr-51f7af318a1b691324ca83ee68751368","url":"https://nvd.nist.gov/vuln/detail/CVE-2021-21283","basis":"official_catalog","notes":"This product uses data from the NVD API but is not endorsed or certified by the NVD.","title":"CVE-2021-21283","publisher":"NIST National Vulnerability Database","observed_at":"2026-10-31T22:07:35.928Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-9bfacdceb041be3a8e068b90185c5892"],"technology":"flarum/sticky","known_exclusions":[],"conditions_summary":"### Impact\nA change in release beta 14 of the Sticky extension caused the plain text content of the first post of a pinned discussion to be injected as HTML on the discussion list. The issue was discovered following an internal audit.\n\nAny HTML would be injected through Mithril's `m.trust()` helper. This resulted in an HTML injection where `` tags would not be executed. However it was possible to run javascript from other HTML attributes, enabling a cross-site scripting (XSS) attack to be performed.\n\nSince the exploit only happens with the first post of a pinned discussion, an attacker would need the ability to pin their own discussion, or be able to edit a discussion that was previously pinned.\n\nOn forums where all pinned posts are authored by your staff, you can be relatively certain the vulnerability has not been exploited.\n\nForums where some user-created discussions were pinned can look at the first post edit date to find whether the vulnerability might have been exploited. Because Flarum doesn't store the post content history, you cannot be certain if a malicious edit was reverted.\n\n### Patches\nThe fix will be available in version v0.1.0-beta.16 with Flarum beta 16. Th","public_affected_ranges":["ECOSYSTEM: introduced 0.1.0-beta.14; fixed 0.1.0-beta.15.1"]}],"null_published_at":"2026-10-31T22:27:06.705Z","source_updated_at":"2026-07-08T05:59:43.051Z","source_disclosed_at":"2021-01-29T18:13:41.000Z","is_synthetic_fixture":false,"null_last_reviewed_at":null,"public_change_summary":"Source facts changed; compare the preserved prior revision.","null_first_observed_at":"2026-10-31T21:42:20.424Z"},{"id":"NVI-00005770","kind":"vulnerability","title":"XSS in Flarum Sticky extension","revision":1,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-h3gg-7wx2-cq3h","CVE-2021-21283"],"plain_summary":"OSV carries this publisher advisory for flarum/sticky. This is an aggregated source copy; consult the original publisher and compare update dates.","review_status":"source_listed","control_topics":[],"public_actions":[{"summary":"The original advisory lists fixed boundaries 0.1.0-beta.15.1 for flarum/sticky. Confirm the publisher’s latest guidance.","source_ids":["sr-9bfacdceb041be3a8e068b90185c5892"],"action_type":"vendor_patch","limitations":"Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system.","current_supported_target":null}],"schema_version":"1.1.0","source_metrics":[],"why_it_matters":"Published affected context helps an owner decide what evidence to gather. This report has not examined your application.","related_sources":[{"id":"sr-9bfacdceb041be3a8e068b90185c5892","url":"https://github.com/advisories/GHSA-h3gg-7wx2-cq3h","basis":"vendor_advisory","notes":"GitHub-origin advisory, CC-BY-4.0; OSV is an aggregate copy, not independent corroboration.","title":"GHSA-h3gg-7wx2-cq3h","publisher":"GitHub Advisory Database via OSV","observed_at":"2026-10-31T21:42:20.424Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-9bfacdceb041be3a8e068b90185c5892"],"technology":"flarum/sticky","known_exclusions":[],"conditions_summary":"### Impact\nA change in release beta 14 of the Sticky extension caused the plain text content of the first post of a pinned discussion to be injected as HTML on the discussion list. The issue was discovered following an internal audit.\n\nAny HTML would be injected through Mithril's `m.trust()` helper. This resulted in an HTML injection where `` tags would not be executed. However it was possible to run javascript from other HTML attributes, enabling a cross-site scripting (XSS) attack to be performed.\n\nSince the exploit only happens with the first post of a pinned discussion, an attacker would need the ability to pin their own discussion, or be able to edit a discussion that was previously pinned.\n\nOn forums where all pinned posts are authored by your staff, you can be relatively certain the vulnerability has not been exploited.\n\nForums where some user-created discussions were pinned can look at the first post edit date to find whether the vulnerability might have been exploited. Because Flarum doesn't store the post content history, you cannot be certain if a malicious edit was reverted.\n\n### Patches\nThe fix will be available in version v0.1.0-beta.16 with Flarum beta 16. Th","public_affected_ranges":["ECOSYSTEM: introduced 0.1.0-beta.14; fixed 0.1.0-beta.15.1"]}],"null_published_at":"2026-10-31T22:13:05.838Z","source_updated_at":"2026-07-08T05:59:43.051Z","source_disclosed_at":"2021-01-29T18:13:41.000Z","is_synthetic_fixture":false,"null_last_reviewed_at":null,"public_change_summary":"First indexed by Null; source disclosure date is shown separately.","null_first_observed_at":"2026-10-31T21:42:20.424Z"}],"next_cursor":null,"snapshot_revision":"42594"}