CVE-2026-73303

Received Received - Intake

Email Change Hijacking in Budibase

Publication date: 2026-08-12

Last updated on: 2026-08-12

Assigner: GitHub, Inc.

Description

Budibase is an open-source low-code platform. Prior to 3.40.0, POST /api/v2/email on account.budibase.app accepted a client-controlled accountId without binding it to the authenticated session, while checking only currentEmail. An authenticated attacker who obtains a victim account identifier can start the email-change workflow for the victim, receive and submit the verification code through POST /api/v2/email/verification, move the victim email to an attacker-controlled address, and complete a password reset as the victim. This issue is fixed in version 3.40.0.

CVSS Scores

EPSS Scores

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Meta Information

Published

2026-08-12

Last Modified

2026-08-12

Generated

2026-09-02

AI Q&A

2026-08-13

EPSS Evaluated

2026-08-31

NVD

CVE-2026-73303

EUVD

EUVD-2026-57426

Affected Vendors & Products

Vendor	Product	Version / Range
budibase	budibase	to 3.40.0 (exc)

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-639	The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data.

Attack-Flow Graph

Executive Summary

This is an Insecure Direct Object Reference (IDOR) vulnerability in Budibase's account portal. An attacker with a victim's account identifier (accountId) can initiate an email-change workflow for the victim without proper session binding. The attacker receives the verification code, changes the victim's email to an attacker-controlled address, and completes a password reset to take over the victim's account.

Detection Guidance

To detect this vulnerability, monitor network traffic for POST requests to /api/v2/email with mismatched accountId and session accountId. Check Budibase server logs for unusual email change workflows or verification code submissions. Ensure your Budibase version is 3.40.0 or later to confirm the fix is applied.

Impact Analysis

An attacker could gain full access to your Budibase account, including all tenants, apps, and stored credentials. They could lock you out of your own account and perform actions on your behalf. The attack requires obtaining your accountId through out-of-band means but is otherwise reliable once that is done.

Compliance Impact

This vulnerability could lead to unauthorized access to sensitive user data, which may violate compliance requirements under GDPR (e.g., unauthorized data access or processing) and HIPAA (e.g., unauthorized access to protected health information). The full account takeover allows attackers to exfiltrate or manipulate data, posing significant risks to data integrity and confidentiality.

Mitigation Strategies

Upgrade Budibase to version 3.40.0 or later to address the vulnerability. Validate that the accountId in POST /api/v2/email matches the authenticated session's accountId before processing email changes.

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