Missing Authentication for Critical Function Affecting symfony/mailtrap-mailer package, versions <7.4.12>=8.0.0-BETA1, <8.0.12
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- published24 May 2026
- disclosed20 May 2026
- creditHimanshu Anand
Introduced: 20 May 2026
NewCVE-2026-45755 (opens in a new tab)How to fix?
Upgrade symfony/mailtrap-mailer to version 7.4.12, 8.0.12 or higher.
Overview
symfony/mailtrap-mailer is a Symfony Mailtrap Mailer Bridge
Affected versions of this package are vulnerable to Missing Authentication for Critical Function via the doParse() webhook request parser in the Mailtrap mailer bridge. An attacker can submit forged webhook events because the parser ignores the X-Mt-Signature HMAC header and never validates the configured webhook secret, allowing unauthenticated POST requests to be processed as legitimate Mailtrap callbacks.
This can lead to falsified delivery, bounce, open, click, or spam events, resulting in suppression-list corruption and delivery-metrics manipulation.