Authorization Bypass Through User-Controlled Key Affecting winter/wn-backend-module package, versions <1.2.13
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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- published29 Aug 2026
- disclosed20 Aug 2026
- creditUnknown
Introduced: 20 Aug 2026
NewCVE-2026-54256 (opens in a new tab)How to fix?
Upgrade winter/wn-backend-module to version 1.2.13 or higher.
Overview
Affected versions of this package are vulnerable to Authorization Bypass Through User-Controlled Key via the FileUpload process. An attacker can gain unauthorized access to and modify metadata and ordering of attachments belonging to other users by submitting crafted file_id parameters to backend endpoints. This is only exploitable if the attacker is an authenticated backend user with access to a form containing a fileupload field.