Auth bypass in /Mailtrap-Mailer Mailtrap-Mailer
CVE-2026-45755
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.
Vulnerability class: Broken Authentication
EPSS: 0.003 (18.4th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N.
Affected products
- /Mailtrap-mailer Mailtrap-mailer — versions >= 7.2.0, < 7.4.12, >= 8.0.0-BETA1, < 8.0.12
- Sensiolabs Symfony
- Symfony — versions >= 7.2.0, < 7.4.12, >= 8.0.0-BETA1, < 8.0.12
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Patch, Vendor Advisory)
- security-advisories@github.com (Patch, x_refsource_MISC)
- security-advisories@github.com (Product, x_refsource_MISC, Release Notes)
- security-advisories@github.com (Product, x_refsource_MISC, Release Notes)
Frequently asked questions
- What is CVE-2026-45755?
- CVE-2026-45755 is a medium-severity vulnerability in /Mailtrap-Mailer Mailtrap-Mailer, classified under Missing Authentication for Critical Function. CVSS score: 5.3/10. Published 2026-07-14.
- How severe is CVE-2026-45755?
- Medium severity. CVSS v3 base score is 5.3 out of 10.