{"id":"CVE-2026-55696","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-55696","generatedAt":"2026-10-28T09:26:36.767Z","title":"Prior to 2.0.5, AttachmentViewer.setAttachment in js/privatebin.js uses getAttachmentMimeType to accept attacker-controlled MIME types and uses getBlobUrl to create a same-origin blob before setting attachmentLink's href for the Download attachment link.","description":"PrivateBin is an online pastebin where the server has zero knowledge of pasted data. Prior to 2.0.5, AttachmentViewer.setAttachment in js/privatebin.js uses getAttachmentMimeType to accept attacker-controlled MIME types and uses getBlobUrl to create a same-origin blob before setting attachmentLink's href for the Download attachment link. The SVG-only sanitization branch updates only the preview blob, so text/html, image/svg, application/xhtml+xml, and text/xml attachments can remain active in the download blob. On an instance with fileupload = true and a weakened, stripped, or absent Content Security Policy, an anonymous attacker can create such an attachment, and a victim who opens the link in a new tab causes inline JavaScript to execute in the PrivateBin origin. The script can read origin-scoped local storage and issue same-origin requests, including requests to applications co-hosted on the same domain. This issue is fixed in version 2.0.5.","published":"2026-08-28T22:16:52.000Z","lastModified":"2026-09-09T21:09:13.000Z","status":"Deferred","sourceIdentifier":"security-advisories@github.com","cvss":{"version":"3.1","score":4.3,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N"},"cwe":["CWE-79","CWE-80"],"affected":[],"epss":{"score":0.00368,"percentile":0.30481,"date":"2026-10-27","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (0.37%). Track it; it rarely justifies an emergency change on its own."},"changes":[],"references":[{"url":"https://github.com/PrivateBin/PrivateBin/commit/7f1f40853efe0eb12db9cc4a30ea8524ac00f423","source":"security-advisories@github.com"},{"url":"https://github.com/PrivateBin/PrivateBin/releases/tag/2.0.5","source":"security-advisories@github.com"},{"url":"https://github.com/PrivateBin/PrivateBin/security/advisories/GHSA-f2xf-7x3g-4272","source":"security-advisories@github.com"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-55696","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}