CVE-2026-115480
Deferred
Deferred - Pending Action
Unauthenticated CAPTCHA Bypass in baserCMS API
Vulnerability report for CVE-2026-115480, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-10-23
Last updated on: 2026-10-23
Assigner: GitHub, Inc.
Description
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.
CVSS Scores
EPSS Scores
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| Percentile: |
Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| baserproject | basercms | >= 5.0.0, < 5.3.2 |
| baserproject | basercms | >= 5.4.0, < 5.4.2 |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-693 | The product does not use or incorrectly uses a protection mechanism that provides sufficient defense against directed attacks against the product. |
| CWE-799 | The product does not properly limit the number or frequency of interactions that it has with an actor, such as the number of incoming requests. |
