CVE-2026-55696
PrivateBin: Stored Cross-Side-Scripting (XSS) vulnerability in attachment download link via dangerous MIME types with required user-interaction
- Published
- Updated
- Reserved
- Assigned by
- GitHub_M
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.
Timeline
ID reserved
By GitHub_M
- 2 months later
· 2 months later
Published
- 3 days later
· 3 days later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | Medium4.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N |
| NVDNVD · Deferred | 3.1 | Medium4.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N |
- EPSS (exploitation in 30 days)
- 0.44% · top 62% of all CVEs (7 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 4.3.
Weakness
Affected products
- affected < 2.0.5
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- Packagistprivatebin/privatebinGHSA-f2xf-7x3g-4272 (opens in a new tab)
References (3)
- https://github.com/PrivateBin/PrivateBin/security/advisories/GHSA-f2xf-7x3g-4272 (opens in a new tab)x_refsource_CONFIRM
- https://github.com/PrivateBin/PrivateBin/commit/7f1f40853efe0eb12db9cc4a30ea8524ac00f423 (opens in a new tab)x_refsource_MISC
- https://github.com/PrivateBin/PrivateBin/releases/tag/2.0.5 (opens in a new tab)x_refsource_MISC
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-f2xf-7x3g-4272 (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2026-55696)Record last updated .