CVE-2026-30878 baserCMS: Mail Form Acceptance Bypass via Public API

Medium 5.3 Published 31 Mar 2026 Updated 31 Mar 2026

Unauthenticated users can bypass administrative controls to submit mail forms via the public API, enabling spam and abuse.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: Available

What is CVE-2026-30878?

CVE-2026-30878 is a medium-severity missing authorization vulnerability in Basercms Basercms, published on 31 Mar 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

baserCMS is a website development framework. Prior to version 5.2.3, a public mail submission API allows unauthenticated users to submit mail form entries even when the corresponding form is not accepting submissions. This bypasses administrative controls intended to stop form intake and enables spam or abuse via the API. This issue has been patched in version 5.2.3.

Weakness: CWE-285

Which versions are affected by CVE-2026-30878?

2 open source packages ship an affected version, including baserproject/basercms. It affects 1 product.

Package	Affected	Fixed in
`baserproject/basercms` Packagist	All versions	`5.2.3`
`baserproject/basercms` Packagist	All versions	`5.2.3`

Products include Basercms Basercms.

How do I fix CVE-2026-30878?

Upgrade baserproject/basercms to 5.2.3 or later.

Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.

Is CVE-2026-30878 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-30878 exists.

All Basercms Basercms vulnerabilities

Sources

Also known as GHSA-8cr7-r8qw-gp3c.