Frappe ERPNext Signup press.api.account.signup email input validation

Summaryinfo

A vulnerability described as critical has been identified in Frappe ERPNext. This vulnerability affects unknown code of the file /api/method/press.api.account.signup of the component Signup. The manipulation of the argument email results in input validation. This vulnerability was named CVE-2026-4894. The attack may be performed from remote. There is no available exploit.

Detailsinfo

A vulnerability, which was classified as critical, was found in Frappe ERPNext (unknown version). Affected is an unknown code block of the file /api/method/press.api.account.signup of the component Signup. The manipulation of the argument email with an unknown input leads to a input validation vulnerability. CWE is classifying the issue as CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

A vulnerability has been identified regarding insufficient validation in the Frappe Cloud/ERPNext authentication process, which allows multiple email addresses to be accepted by manipulating the email field in the /api/method/press.api.account.signup endpoint. The vulnerability occurs when an unauthenticated remote attacker adds more than one email address. The service processes the entire value as a valid list of recipients and sends the OTP code to all addresses without proper validation of all added emails (only one of them needs to be valid). Exploiting this vulnerability would allow an attacker to: * Obtain the authentication OTP; * Impersonate someone else in the registration process; * Register accounts using other people's email addresses without access to the mailbox; * Indirectly confirm the existence of already registered email addresses.

The advisory is shared for download at incibe.es. This vulnerability is traded as CVE-2026-4894 since 03/26/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 10/08/2026).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

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Vendor

• Frappe

Name

• ERPNext

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CPE 2.2info

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