Craft CMS 5.0.0-RC1 before 5.10.11 File Overwrite via assets/replace-file (CVE-2026-84800) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-84800

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

Answer in brief

CVE-2026-84800 records a Unknown severity vulnerability in Craft CMS 5.0.0-RC1 before 5.10.11 File Overwrite via assets/replace-file. The current sources do not mark it as known exploited. The current feed maps craftcms/cms (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 2, 2026Updated Sep 2, 2026Source checked Sep 2, 2026First seen by HOL Sep 2, 2026Material review Sep 2, 2026

Upstream Advisory

Key facts

Risk: Unknown severitySource severity not reported
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Available

Why this deserves its current priority

A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps craftcms/cms (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
craftcms/cmsgeneric	>=5.0.0-RC1 <5.10.11	5.10.11

Recommended response

Check inventory. Check lockfiles and deployed manifests for craftcms/cms.
Review the reported fix. Update craftcms/cms to 5.10.11 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Sep 2, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 2, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 2, 2026

Sources and claim methodology

Upstream source 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.

Quoted source text, attributed separately from HOL analysis.