XSS in Gitroom Postiz
CVE-2026-40487
Postiz is an AI social media scheduling tool. Prior to version 2.21.6, a file upload validation bypass allows any authenticated user to upload arbitrary HTML, SVG, or other executable file types to the server by spoofing the `Content-Type`…
Vulnerability class: XSS (Cross-Site Scripting)
EPSS: 0.002 (13.2th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 8.9 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:L.
Affected products
- Gitroom Postiz
- Gitroomhq Postiz-app — versions < 2.21.6
Weakness classification (CWE)
Public proof-of-concept exploits
References
- security-advisories@github.com (x_refsource_CONFIRM, Exploit, Vendor Advisory)
- security-advisories@github.com (Product, x_refsource_MISC, Release Notes)
Frequently asked questions
- What is CVE-2026-40487?
- CVE-2026-40487 is a high-severity vulnerability in Gitroom Postiz, classified under Cross-site Scripting. CVSS score: 8.9/10. Published 2026-04-18.
- How severe is CVE-2026-40487?
- High severity. CVSS v3 base score is 8.9 out of 10.
- Is CVE-2026-40487 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.