CVE-2026-45755: Sensiolabs Symfony

Medium severity, CVSS 5.3. EPSS: 0.3% chance of exploitation in the next 30 days.

Symfony is a PHP framework for web and console applications and a set of reusable PHP components. Prior to 7.4.12 and 8.0.12, MailtrapRequestParser::doParse() received the configured webhook secret but ignored the X-Mt-Signature HMAC header, allowing unauthenticated POST requests to inject forged Mailtrap delivery, bounce, open, click, or spam events. This issue is fixed in versions 7.4.12 and 8.0.12.

Affected products

• Sensiolabs Symfony: from 7.2.0, before 7.4.12 (fixed in 7.4.12); from 8.0.0, before 8.0.12 (fixed in 8.0.12)

Published 2026-07-14. Last modified 2026-07-15.