{"id":"CVE-2026-48822","state":"PUBLISHED","title":"Shaarli has Stored Cross-Site Scripting (XSS) via Markdown Reference Links","description":"Shaarli is a personal bookmarking service. Versions 0.16.1 and prior contain a stored Cross-Site Scripting (XSS) vulnerability in the Markdown-to-HTML conversion process used in the Bookmark Description field. An authenticated user can inject a malicious javascript: URI inside a Markdown link. The vulnerability originates in the filterProtocols method within BookmarkMarkdownFormatter.php.This method attempts to sanitize Markdown links by filtering dangerous protocols (such as javascript:) before rendering. It uses the following regular expression: (#]\\((.*?)\\)#is). This regex is designed to detect inline Markdown links, but it fails to detect Markdown reference-style links because reference-style links are resolved by the Markdown parser after preprocessing. The filterProtocols method never inspects the actual URL used in these references and as a result, an attacker can supply a javascript: URI inside a reference definition. This issue has been fixed in version 0.16.2.","publishedAt":"2026-06-17T19:59:34.277Z","updatedAt":"2026-06-18T15:42:42.133Z","severity":{"score":5.8,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:H/UI:R/S:U/C:H/I:H/A:N","source":"GitHub_M"},"assigner":"GitHub_M","products":["shaarli Shaarli"],"affected":[{"vendor":"shaarli","product":"Shaarli","versions":[{"version":"< 0.16.2","status":"affected"}]}],"references":["https://github.com/shaarli/Shaarli/security/advisories/GHSA-2hgr-63wv-x462","https://github.com/shaarli/Shaarli/releases/tag/v0.16.2"],"weaknesses":["CWE-79"],"ingestedAt":"2026-10-29T20:12:07.131Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/48xxx/CVE-2026-48822.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-48822","state":"PUBLISHED","datePublished":"2026-06-17T19:59:34.277Z","dateUpdated":"2026-06-18T15:42:42.133Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-05-22T20:57:10.977Z"},"containers":{"cna":{"title":"Shaarli has Stored Cross-Site Scripting (XSS) via Markdown Reference Links","descriptions":[{"lang":"en","value":"Shaarli is a personal bookmarking service. Versions 0.16.1 and prior contain a stored Cross-Site Scripting (XSS) vulnerability in the Markdown-to-HTML conversion process used in the Bookmark Description field. An authenticated user can inject a malicious javascript: URI inside a Markdown link. The vulnerability originates in the filterProtocols method within BookmarkMarkdownFormatter.php.This method attempts to sanitize Markdown links by filtering dangerous protocols (such as javascript:) before rendering. It uses the following regular expression: (#]\\((.*?)\\)#is). This regex is designed to detect inline Markdown links, but it fails to detect Markdown reference-style links because reference-style links are resolved by the Markdown parser after preprocessing. The filterProtocols method never inspects the actual URL used in these references and as a result, an attacker can supply a javascript: URI inside a reference definition. This issue has been fixed in version 0.16.2."}],"affected":[{"vendor":"shaarli","product":"Shaarli","versions":[{"version":"< 0.16.2","status":"affected"}]}],"references":[{"url":"https://github.com/shaarli/Shaarli/security/advisories/GHSA-2hgr-63wv-x462","name":"https://github.com/shaarli/Shaarli/security/advisories/GHSA-2hgr-63wv-x462","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/shaarli/Shaarli/releases/tag/v0.16.2","name":"https://github.com/shaarli/Shaarli/releases/tag/v0.16.2","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"LOCAL","availabilityImpact":"NONE","baseScore":5.8,"baseSeverity":"MEDIUM","confidentialityImpact":"HIGH","integrityImpact":"HIGH","privilegesRequired":"HIGH","scope":"UNCHANGED","userInteraction":"REQUIRED","vectorString":"CVSS:3.1/AV:L/AC:L/PR:H/UI:R/S:U/C:H/I:H/A:N","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-79","lang":"en","description":"CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-06-17T19:59:34.277Z"},"source":{"advisory":"GHSA-2hgr-63wv-x462","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/shaarli/Shaarli/security/advisories/GHSA-2hgr-63wv-x462","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-06-18T15:35:27.903553Z","id":"CVE-2026-48822","options":[{"Exploitation":"poc"},{"Automatable":"no"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-06-18T15:42:42.133Z"}}]}}}