Strapi 4.1.12 Cross-site Scripting via crafted file

published 2022-07-13 4 y ago modified 2026-07-02 4 mo ago also GHSA-4vm8-j95f-j6v5 , EUVD-2022-6232

cvss: 8.8; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 2.0%; EPSS 2.0% chance of exploitation in 30 days, percentile 80%
public exploits: 0; none known

An unrestricted file upload vulnerability in the Add New Assets function of Strapi 4.1.12 allows attackers to conduct XSS attacks via a crafted PDF file. NOTE: the project documentation suggests that a user with the Media Library "Create (upload)" permission is supposed to be able to upload PDF files containing JavaScript, and that all files in a public assets folder are accessible to the outside world (unless the filename begins with a dot character). The administrator can choose to allow only image, video, and audio files (i.e., not PDF) if desired.

Exploit prediction

1.97% chance of exploitation in the next 30 days, higher than 80% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

grimthereaperteam.medium.com https://grimthereaperteam.medium.com/strapi-v4-1-12-unrestricted-file-upload-b993bfd07e4e referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
NVD	3.1	8.8	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
NVD	2.0	6.5	AV:N/AC:L/Au:S/C:P/I:P/A:P
GitHub	3.1	4.6	CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N

Affected packages

ecosystem	package	affected	fixed in
npm	@strapi/strapi	<=4.1.12	no fix listed

Classification

Weakness

CWE-434 Unrestricted Upload of File with Dangerous Type
CWE-79 Improper Neutralization of Input During Web Page Generation

References

Sources

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.

Summary