CVE-2025-56236: FormCms avatar upload feature has a stored cross-site scripting (XSS) vulnerability

August 28, 2025

FormCms v0.5.5 contains a stored cross-site scripting (XSS) vulnerability in the avatar upload feature. Authenticated users can upload .html files containing malicious JavaScript, which are accessible via a public URL. When a privileged user accesses the file, the script executes in their browser context.

References

github.com/FormCms/FormCms/issues/27
github.com/KKC73/me/blob/main/CVE-2025-56236/README.md
github.com/advisories/GHSA-4fxf-xgrm-8fcj
github.com/formcms/formcms
nvd.nist.gov/vuln/detail/CVE-2025-56236

Code Behaviors & Features

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