{"id":"CVE-2026-103974","revision":"ad754e2a4a964c9b929e174688ae8fa4","records":[{"revision":"ad754e2a4a964c9b929e174688ae8fa4","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-103974","aliases":[],"title":"lichess.org: Stored HTML Injection via PGN Annotator Tag in Studies","description":"lichess.org is the forever free, adless and open source chess server. Prior to commit c54596c9e1569d378fe20f80d4c790c6fdee54c4, a user who can add a chapter to a study can place attacker-controlled text in the PGN Annotator tag, which becomes Comment.Author.External and is returned verbatim by authorText. When a study node has at least two comments, ui/analyse/src/treeView/inlineView.ts interpolates that author string into HTML passed to the innerHTML hook without escaping it. Opening the affected study can therefore render stored attacker-controlled HTML and CSS for other viewers, including navigation to an attacker-controlled site, content spoofing, and CSS-based data exposure, although the site's content security policy blocks injected JavaScript. This vulnerability is fixed by commit c54596c9e1569d378fe20f80d4c790c6fdee54c4.","state":0,"publishedAt":"2026-10-14T18:17:13.77+00:00","modifiedAt":"2026-10-14T19:41:15.577+00:00","affected":[{"ecosystem":"Vendor product","name":"lila","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"lichess-org\",\n                    \"product\": \"lila\",\n                    \"versions\": [\n                        {\n                            \"version\": \"< c54596c9e1569d378fe20f80d4c790c6fdee54c4\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 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,"severity":"MEDIUM"}],"references":["https://github.com/lichess-org/lila/security/advisories/GHSA-43g7-r6hp-ccf8","https://github.com/lichess-org/lila/commit/c54596c9e1569d378fe20f80d4c790c6fdee54c4"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-103974","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-103974","identifiers":["CVE-2026-103974"]},"retained":false,"historicalAffected":[]}],"coverage":[]}