Dromara free-fs 2.0.1 through 2.3.1 Stored XSS via File Preview Endpoint

Advisories

Dromara free-fs 2.0.1 through 2.3.1 Stored XSS via File Preview Endpoint

Severity: medium
Date: 11/13/2026
Affecting: free-fs >= 2.0.1, <= 2.3.1
CVE: CVE-2026-129163
CWE: CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CVSS: 5.1
CVSS V4 Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N
References: https://vul.yulun.ac.cn/20261024/free-fs/
https://github.com/dromara/free-fs/issues/28
https://github.com/dromara/free-fs/blob/f8f4ff2a0b0af8fcd5cbecbf99a4afb7d0b7c020/fs-modules/fs-file/src/main/java/com/xddcodec/fs/file/controller/FileStreamController.java#L209-L237
Credit: Wu Yulun
Description: Dromara free-fs 2.0.1 through 2.3.1 contains a stored cross-site scripting vulnerability that allows registered users to run script by uploading HTML files served inline as text/html. Attackers can send a victim the /api/file/stream/preview/{fileId} link to execute script in the application origin, calling /apis endpoints to expose the victim's files and account.

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