CVE-2026-45754: Symfony's Mailjet Mailer Webhook Parser Never Verifies the Configured Secret — Unauthenticated Webhook Event Injection

medium Affects symfony/lox24-notifier, symfony/mailjet-mailer, symfony/symfony. Feed 2026.10.29.1, updated 2026-10-28; published 2026-05-28; advisory modified 2026-09-10.

Symfony's Mailjet Mailer Webhook Parser Never Verifies the Configured Secret — Unauthenticated Webhook Event Injection

Package: symfony/lox24-notifier Composer
Affected versions: >=7.1.0 and <7.4.12 or >=8.0.0 and <8.0.12 or >=7.1.0 and <7.2.0 or >=7.2.0 and <7.3.0 or >=7.3.0 and <7.4.0 or >=7.4.0 and <7.4.12
Fixed in: 7.4.12, 8.0.12
Severity: medium
Exploitation: not on CISA KEV · EPSS 0% (38.6th percentile)
Published: 2026-05-28
Source: osv.dev

References

Symfony's Mailjet Mailer Webhook Parser Never Verifies the Configured Secret — Unauthenticated Webhook Event Injection

Package: symfony/mailjet-mailer Composer
Affected versions: >=6.4.0 and <6.4.40 or >=7.0.0 and <7.4.12 or >=8.0.0 and <8.0.12 or >=7.0.0 and <7.1.0 or >=7.1.0 and <7.2.0 or >=7.2.0 and <7.3.0 or >=7.3.0 and <7.4.0 or >=7.4.0 and <7.4.12
Fixed in: 6.4.40, 7.4.12, 8.0.12
Severity: medium
Exploitation: not on CISA KEV · EPSS 0% (38.6th percentile)
Published: 2026-05-28
Source: osv.dev

References

Symfony's Mailjet Mailer Webhook Parser Never Verifies the Configured Secret — Unauthenticated Webhook Event Injection

Package: symfony/symfony Composer
Affected versions: >=6.4.0 and <6.4.40 or >=7.0.0 and <7.4.12 or >=8.0.0 and <8.0.12 or >=7.0.0 and <7.1.0 or >=7.1.0 and <7.2.0 or >=7.2.0 and <7.3.0 or >=7.3.0 and <7.4.0 or >=7.4.0 and <7.4.12
Fixed in: 6.4.40, 7.4.12, 8.0.12
Severity: medium
Exploitation: not on CISA KEV · EPSS 0% (38.6th percentile)
Published: 2026-05-28
Source: osv.dev

References

CWE-287 CWE-306

NVD record symfony/lox24-notifier advisories symfony/mailjet-mailer advisories symfony/symfony advisories

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