CVE-2026-84800
Craft CMS 5.0.0-RC1 before 5.10.11 File Overwrite via assets/replace-file
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.
INFO
Published Date :
Sept. 2, 2026, 12:17 p.m.
Last Modified :
Sept. 2, 2026, 2:17 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | HIGH | 83251b91-4cc7-4094-a5c7-464a1b83ea10 | ||||
| CVSS 3.1 | HIGH | MITRE-CVE | ||||
| CVSS 3.1 | HIGH | [email protected] | ||||
| CVSS 4.0 | HIGH | 83251b91-4cc7-4094-a5c7-464a1b83ea10 | ||||
| CVSS 4.0 | HIGH | [email protected] |
Solution
- Update Craft CMS to version 5.10.11.
- Verify that the replacePeerFiles permission is enforced.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-84800.
| URL | 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 |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-84800 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-84800
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-84800 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-84800 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Sep. 02, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-84800', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-09-02T13:17:30.955435Z'} -
New CVE Received by [email protected]
Sep. 02, 2026
Action Type Old Value New Value Added 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. Added CVSS V4.0 AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:L Added CWE CWE-862 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/84xxx/CVE-2026-84800.json">CVE-2026-84800</a> Added Reference https://github.com/craftcms/cms/security/advisories/GHSA-329j-cx85-8r56 Added Reference https://www.vulncheck.com/advisories/craft-cms-5.0.0-rc1-before-5.10.11-file-overwrite-via-assets-replace-file