CVE-2026-84800

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 v3 7.1 HIGH

7.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 4.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/craftcms/cms/security/advisories/GHSA-329j-cx85-8r56
https://www.vulncheck.com/advisories/craft-cms-5.0.0-rc1-before-5.10.11-file-overwrite-via-assets-replace-file

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-02 12:17

Updated : 2026-09-02 14:17

NVD link : CVE-2026-84800

Mitre link : CVE-2026-84800

CVE.ORG link : CVE-2026-84800

JSON object : View

Products Affected

No product.

CWE

CWE-862

Missing Authorization

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