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
Published · last modified .
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.
EPSS exploit prediction
EPSS: 0.003 (17.4th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 17th percentile — 17.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000
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
- github.com/symfony/symfony/security/advisories/GHSA-59f3-vp2f-mp9w (Patch, Vendor Advisory)
- github.com/symfony/symfony/commit/4e0467e4e182cf2e704a3d9e1bc1a6be65d52ab8 (Patch)
- github.com/symfony/symfony/releases/tag/v7.4.12 (Product, Release Notes)
- github.com/symfony/symfony/releases/tag/v8.0.12 (Product, 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.