CVE-2026-35451 json
Twenty: Stored XSS via BlockNote FileBlock
published 2026-04-21 6 mo ago modified 2026-10-26 13 d ago also EUVD-2026-24161
- cvss
- 5.7
- 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 23%
- public exploits
- 0
- none known
Summary
Twenty is an open source CRM. Prior to 1.20.6, a Stored Cross-Site Scripting (XSS) vulnerability exists in the BlockNote editor component. Due to a lack of protocol validation in the FileBlock component and insufficient server-side inspection of block content, an attacker can inject a javascript: URI into the url property of a file block. This allows the execution of arbitrary JavaScript when a user clicks on the malicious file attachment. This vulnerability is fixed in 1.20.6.
Patch / fix
CISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- no
- Technical impact
- partial
- Assessed
- 6 mo ago
Exploit prediction
0.31% chance of exploitation in the next 30 days, higher than 23% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- github.com https://github.com/twentyhq/twenty/security/advisories/GHSA-7w89-7q26-gj7q referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 5.7 | CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N |
Affected products
- twentyhq twenty
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
References
Sources
- CVE List CVE-2026-35451
- NVD CVE-2026-35451
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