Skip to content
Fencer Intel
high 8.7

CVE-2026-44729 json

Twenty: Stored Cross-Site Scripting via Unsanitized File Serving (Missing Content-Type/Content-Disposition Headers)

published 5mo ago modified 3mo ago also EUVD-2026-31895

cvss
8.7
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 17%
public exploits
0
none known

Summary

Twenty is an open source CRM. In 1.18.0 and earlier, the file serving endpoints in Twenty CRM at /files/* and /file/:fileFolder/:id serve uploaded files using fileStream.pipe(res) without setting any Content-Type, Content-Disposition, or X-Content-Type-Options response headers. This allows an authenticated attacker to upload an HTML file containing JavaScript, which will be rendered by the victim's browser in the context of the Twenty CRM domain when accessed — enabling session hijacking, account takeover, and data theft.

Is CVE-2026-44729 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

Check with Fencer

CISA SSVC

Exploitation
Proof of concept is public
Automatable
no
Technical impact
total
Assessed
5mo ago

Exploit prediction

0.26% chance of exploitation in the next 30 days, higher than 17% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • github.com https://github.com/twentyhq/twenty/security/advisories/GHSA-f5h2-3qw5-3qp7 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 8.7 CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N

Affected products

  • twentyhq twenty

Classification

Weakness
  • CWE-79 Improper Neutralization of Input During Web Page Generation

References

Sources

Fencer Intel 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.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.