Vulnerability · Published Sep 2, 2026 · Assigned by VulnCheck

CVE-2026-84800Craft CMS 5.0.0-RC1 before 5.10.11 File Overwrite via assets/replace-file

High 7.1

In plain English

A high-severity missing authorization in cms from craftcms. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 29% of all known vulnerabilities).

Severity (CVSS 3.1)7.1High

Exploit odds (30 days)0.4%top 71.0% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official 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.

Affected products (as reported)

Vendor	Product	Versions
craftcms	cms	5.0.0-RC1 – before 5.10.11

Weakness: CWE-862 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:L

References

GitHub Security Advisory (GHSA-329j-cx85-8r56) vendor-advisory
VulnCheck Advisory: Craft CMS 5.0.0-RC1 before 5.10.11 File Overwrite via assets/replace-file third-party-advisory