Budibase before 3.40.0 Authentication Bypass via Tenant Owner Email (CVE-2026-72856) | HOL Guard CVE

High · CVSS 8.1CVE-2026-72856

Budibase before 3.40.0 Authentication Bypass via Tenant Owner Email

Answer in brief

CVE-2026-72856 records a High severity (CVSS 8.1) vulnerability in Budibase before 3.40.0 Authentication Bypass via Tenant Owner Email. The current sources do not mark it as known exploited. The current feed maps Budibase/budibase (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 Aug 13, 2026Updated Aug 31, 2026Source checked Sep 28, 2026First seen by HOL Aug 13, 2026Material review Aug 31, 2026

Upstream Advisory

Key facts

Risk: High · CVSS 8.1
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Available

Why this deserves its current priority

CVSS is 8.1. 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 Budibase/budibase (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
Budibase/budibasegeneric	>=0 <3.40.0	3.40.0

Recommended response

Check inventory. Check lockfiles and deployed manifests for Budibase/budibase.
Review the reported fix. Update Budibase/budibase to 3.40.0 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Aug 13, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Aug 31, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Aug 13, 2026

Sources and claim methodology

Upstream source description

Budibase versions before 3.40.0 contain an authorization/authentication bypass in the PUT /api/global/users/tenant/owner (changeTenantOwnerEmail) endpoint. On self-hosted instances (SELF_HOSTED or DISABLE_ACCOUNT_PORTAL set), the cloudRestricted middleware is a no-op and the route is protected only by a general authentication check, so any authenticated user — including a lowest-privilege BASIC app user — can reassign the tenant account-holder (top-privilege admin) email to an attacker-controlled address. The attacker can then use the public password-reset flow to take over the admin account, leading to full administrative access.

Quoted source text, attributed separately from HOL analysis.