CVE-2026-84800: Missing Authorization in craftcms cms
Description
Craft CMS versions >= 5.0.0-RC1 and < 5.10.11 contain a missing authorization vulnerability in AssetsController::actionReplaceFile. When a request supplies sourceAssetId and targetFilename but omits assetId, the target asset is resolved by folder and filename after the permission checks execute, so the replacePeerFiles permission is never enforced. An authenticated low-privilege author with only the replaceFiles permission on a shared folder can overwrite the content of a peer's asset file (located in the same folder) with attacker-controlled bytes. Fixed in 5.10.11.
CVSS v4.0
Score 7.1high
Affected software
craftcms
cms
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
Craft CMS versions >= 5.0.0-RC1 and < 5.10.11 contain a missing authorization vulnerability in the AssetsController::actionReplaceFile method. When a request includes sourceAssetId and targetFilename but omits assetId, the target asset is resolved after permission checks, bypassing enforcement of the replacePeerFiles permission. This allows an authenticated user with only replaceFiles permission on a shared folder to overwrite another user's asset file in that folder with attacker-controlled content. The issue is addressed in version 5.10.11.
Potential Impact
An authenticated user with low privileges (replaceFiles permission) can overwrite peer asset files in the same shared folder, potentially leading to unauthorized content modification. This could affect data integrity and trust in asset contents within the CMS environment.
Mitigation Recommendations
Upgrade Craft CMS to version 5.10.11 or later, where this missing authorization vulnerability is fixed. Patch status is confirmed by the vendor's fixed version. Until upgraded, restrict permissions carefully to avoid granting replaceFiles permission on shared folders to untrusted users.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- VulnCheck
- Date Reserved
- 2026-09-02T10:19:06.331Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6a980702acd9273b492a919d
Added to database: 09/02/2026, 11:22:42 UTC
Last enriched: 09/07/2026, 13:58:34 UTC
Last updated: 10/17/2026, 18:48:23 UTC
Views: 75
Community Reviews
0 reviewsCrowdsource mitigation strategies, share intel context, and vote on the most helpful responses. Sign in to add your voice and help keep defenders ahead.
Want to contribute mitigation steps or threat intel context? Sign in or create an account to join the community discussion.
Actions
Updates to AI analysis require Pro Console access. Upgrade inside Console → Billing.
Need more coverage?
Upgrade to Pro Console for AI refresh and higher limits.
For incident response and remediation, OffSeq services can help resolve threats faster.
Latest Threats
Check if your credentials are on the dark web
Instant breach scanning across billions of leaked records. Free tier available.