CVE-2026-107843: Contao: The registration module re-sends activation mails
ModuleRegistration::compile() reaches its follow-up registration branch on any POST to a page carrying the module. That branch checks neither FORM_SUBMIT nor the captcha result computed immediately above it, and resendActivationMail() leads to OptInToken::send(), which has no rate limit at all.
References
- github.com/advisories/GHSA-mfxh-vp55-7gc6
- github.com/contao/contao/commit/2ea6117f9049db7221679251cfc41e67d941a74b
- github.com/contao/contao/releases/tag/5.3.50
- github.com/contao/contao/releases/tag/5.7.12
- github.com/contao/contao/security/advisories/GHSA-mfxh-vp55-7gc6
- nvd.nist.gov/vuln/detail/CVE-2026-107843
Code Behaviors & Features
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