CVE-2024-56828: File Upload vulnerability in ChestnutCMS through 1.5.0. Based on the code analysis, it was determined that the /api/member/avatar API endpoint...
Description
File Upload vulnerability in ChestnutCMS through 1.5.0. Based on the code analysis, it was determined that the /api/member/avatar API endpoint receives a base64 string as input. This string is then passed to the memberService.uploadAvatarByBase64 method for processing. Within the service, the base64-encoded image is parsed. For example, given a string like: data:image/html;base64,PGh0bWw+PGltZyBzcmM9eCBvbmVycm9yPWFsZXJ0KDEpPjwvaHRtbD4= the content after the comma is extracted and decoded using Base64.getDecoder().decode(). The substring from the 11th character up to the first occurrence of a semicolon (;) is assigned to the suffix variable (representing the file extension). The decoded content is then written to a file. However, the file extension is not validated, and since this functionality is exposed to the frontend, it poses significant security risks.
Classification
CVE ID: CVE-2024-56828
Affected Products
Vendor: n/a
Product: n/a
Exploit Prediction Scoring System (EPSS)
EPSS Score: 0.05% (probability of being exploited)
EPSS Percentile: 17.83% (scored less or equal to compared to others)
EPSS Date: 2025-02-04 (when was this score calculated)
References
https://gitee.com/liweiyi/ChestnutCMShttps://www.1000mz.com/
https://github.com/Zerone0x00/CVE/blob/main/ChestnutCMS/CVE-2024-56828.md