CVE-2026-61843

Deferred Deferred - Pending Action

File Overwrite in FileRise via Shared Links

Publication date: 2026-10-14

Last updated on: 2026-10-15

Assigner: GitHub, Inc.

Description

FileRise is a self-hosted web-based file manager with multi-file upload, editing, and batch operations. Prior to 3.18.0, FileRise upload-enabled shared-folder and upload-only links do not reject a destination filename that already exists. An unauthenticated visitor with a valid share token and any configured share password can upload a file with the same name as an existing file and silently replace its content while the original uploader metadata remains. The same replacement gap affects ordinary authenticated uploads through /api/upload/upload.php and authenticated upload-only users who lack edit authority over the existing file. This issue is fixed in version 3.18.0.

CVSS Scores

EPSS Scores

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Meta Information

Published

2026-10-14

Last Modified

2026-10-15

Generated

2026-10-19

AI Q&A

2026-10-15

EPSS Evaluated

2026-10-18

NVD

CVE-2026-61843

Affected Vendors & Products

Vendor	Product	Version / Range
error311	FileRise	< 3.18.0

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-862	The product does not perform an authorization check when an actor attempts to access a resource or perform an action.

Attack-Flow Graph

Executive Summary

FileRise before version 3.18.0 has a flaw in shared and upload-only links where an attacker can replace existing files by uploading a file with the same name. The original file's metadata remains unchanged, but its content is silently overwritten. This affects both unauthenticated users with share tokens and authenticated users with upload permissions.

Detection Guidance

Detecting this vulnerability requires checking for unauthorized file replacements in FileRise shares or authenticated uploads. Review server logs for duplicate filenames in shared folders or upload directories. Look for discrepancies between file content and metadata timestamps. Compare file hashes before and after uploads to identify silent replacements.

Impact Analysis

This vulnerability allows unauthorized users to replace files without detection, potentially altering critical data like documents or backups. It affects shared links, upload-only users, and authenticated uploads. The impact includes data integrity loss and potential misuse of replaced files.

Compliance Impact

This vulnerability could violate compliance requirements for data integrity and protection, such as GDPR's integrity principle or HIPAA's safeguards for data security. Unauthorized file replacement risks exposing or corrupting sensitive data, leading to potential regulatory penalties.

Mitigation Strategies

Upgrade FileRise to version 3.18.0 or later immediately. Review all shared links and upload directories for unauthorized file replacements. Implement file integrity monitoring to detect changes. Restrict upload permissions to prevent overwrites of existing files.

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