Craft CMS 5.0.0-RC1 before 5.10.12 Permission Escalation via UsersController (CVE-2026-86731) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-86731

Craft CMS 5.0.0-RC1 before 5.10.12 Permission Escalation via UsersController

Answer in brief

CVE-2026-86731 records a Unknown severity vulnerability in Craft CMS 5.0.0-RC1 before 5.10.12 Permission Escalation via UsersController. 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 8, 2026Updated Sep 8, 2026Source checked Sep 8, 2026First seen by HOL Sep 8, 2026Material review Sep 8, 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 <5.10.12	5.10.12

Recommended response

Check inventory. Check lockfiles and deployed manifests for craftcms/cms.
Review the reported fix. Update craftcms/cms to 5.10.12 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Sep 8, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 8, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 8, 2026

Sources and claim methodology

Upstream source description

Craft CMS versions 5.0.0-RC1 through 5.10.11 are missing an admin-target guard in UsersController::actionActivateUser (the users/activate-user action). While the action requires the administrateUsers permission, it does not call requireAdmin() when the targeted user is an administrator, unlike the mirror action actionDeactivateUser. As a result, an authenticated control panel user who is not an administrator but holds the administrateUsers permission can activate a pending or deliberately deactivated administrator account, which can lead to permission escalation when combined with resetting that account's password. The issue is fixed in Craft CMS 5.10.12.

Quoted source text, attributed separately from HOL analysis.