Contao: The registration module re-sends activation mails

[ Description ]Official description

Contao is an Open Source CMS. From version 4.1.0 until 5.3.50 and 5.7.12, ModuleRegistration::compile() enters its follow-up registration branch on any POST to a page containing the registration module without verifying FORM_SUBMIT or the preceding captcha result. resendActivationMail() can then invoke OptInToken::send() without rate limiting, allowing an unauthenticated attacker to cause repeated activation emails to be sent to an address with a pending registration and to determine whether that pending registration exists. The branch is reachable only when reg_activate is enabled and the target has an unconfirmed registration and opt-in token. This issue is fixed in versions 5.3.50 and 5.7.12.

[ Fixes ]Fixes and patches

• contao/core-bundle 5.3.50Fixed version · GitHub Advisories · composer package contao/core-bundle: upgrade to 5.3.50 or later (affected >= 4.1.0, < 5.3.50)
• contao/core-bundle 5.7.12Fixed version · GitHub Advisories · composer package contao/core-bundle: upgrade to 5.7.12 or later (affected >= 5.4.0-RC1, < 5.7.12)

[ Packages ]Affected open-source packages

• contao/core-bundle composerAffected >= 4.1.0, < 5.3.50 · fixed in 5.3.50 · GHSA-mfxh-vp55-7gc6
• contao/core-bundle composerAffected >= 5.4.0-RC1, < 5.7.12 · fixed in 5.7.12 · GHSA-mfxh-vp55-7gc6

[ References ]References

• 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