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

Severity: medium (CVSS 5.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2026-03-31 · updated 2026-06-17
Weakness: CWE-285

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.

Affected products

baserproject basercms: before 5.2.3 — fixed in 5.2.3

How to fix

Upgrade to a fixed version: baserproject basercms 5.2.3. Check the vendor advisory for mitigations.

References

https://basercms.net/security/JVN_20837860
https://github.com/baserproject/basercms/releases/tag/5.2.3
https://github.com/baserproject/basercms/security/advisories/GHSA-8cr7-r8qw-gp3c
https://github.com/baserproject/basercms/security/advisories/GHSA-8cr7-r8qw-gp3c

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