CVE-2026-8623 json
Dear Flipbook <= 2.4.30 - Authenticated (Contributor+) Stored Cross-Site Scripting via '.dvcss' Element Class Attribute
published 2026-09-05 2 mo ago modified 2026-09-08 2 mo ago also EUVD-2026-71837
- cvss
- 6.4
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 28%
- public exploits
- 0
- none known
Summary
The Dear Flipbook – PDF Flipbook, 3D Flipbook, PDF embed, PDF viewer plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'post_content (class attribute of .dvcss element)' parameter in all versions up to, and including, 2.4.30 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. The payload is embedded as a Base64-encoded JSON object in a CSS class name on a Custom HTML block; the frontend parseCSSElements() function decodes it client-side with atob() and JSON.parse() and renders the logo property as raw HTML, meaning no server-side or client-side sanitization intercepts the malicious script before DOM insertion.
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 2 mo ago
Exploit prediction
0.35% chance of exploitation in the next 30 days, higher than 28% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 6.4 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N |
Affected products
- dearhive DearFlip – PDF Flipbook, 3D Flipbook, PDF embed, PDF viewer
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
- Technology feeds
References
- wordfence.com /threat-intel/vulnerabilities/id/27e2848d-6271-4bb9-92e2-0f8c8860745d?source=cve
- plugins.trac.wordpress.org /browser/3d-flipbook-dflip-lite/tags/2.4.27/assets/js/dflip.js#L11255
- plugins.trac.wordpress.org /browser/3d-flipbook-dflip-lite/tags/2.4.27/assets/js/dflip.js#L2687
- plugins.trac.wordpress.org /changeset?reponame=&new=3641463%403d-flipbook-dflip-lite%2Ftags%2F2.4.37&old=3557511%403d-flipbook-dflip-lite
- plugins.trac.wordpress.org /changeset/3641463/3d-flipbook-dflip-lite/trunk/assets/js/dflip.js
- plugins.trac.wordpress.org /changeset?old_path=%2F3d-flipbook-dflip-lite/tags/2.4.30&new_path=%2F3d-flipbook-dflip-lite/tags/2.4.37
Sources
- CVE List CVE-2026-8623
- NVD CVE-2026-8623
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.