Description
baserCMS is a website development framework. In versions 5.0.0 before 5.3.2 and 5.4.0 before 5.4.2, the public POST /baser/api/bc-mail/mail_messages/add/{mailContentId}.json endpoint accepts submissions without enforcing the form's auth_captcha setting. BcMail\Controller\Api\MailMessagesController::add() and MailMessagesService::create() omit the BcCaptchaService::check() verification of captcha_id and auth_captcha performed by MailController::submit() in the web UI. An unauthenticated attacker who can reach the API can therefore automate submissions without solving the enabled image challenge. The API disables FormProtection and has no rate limit; submissions can generate administrator-inbox spam, send attacker-influenced auto-replies to third parties when an email field is present, and accumulate mail_messages database records when save_info is enabled. The API already enforces the isAccepting() check added for CVE-2026-30878; the missing CAPTCHA check is a separate control failure. This issue has been patched in versions 5.3.2 and 5.4.2.
References5
Metrics
- CVSS 3.1
-
5.3
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N - EPSS — exploit probability
- 0% percentile: 25 · as of 8 November 2026
- CWE
- CWE-693CWE-799
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