{"id":"CVE-2026-45755","aliases":["GHSA-59f3-vp2f-mp9w"],"url":"https://o3.security/vulnerability/CVE-2026-45755","summary":"Symfony: Mailtrap Mailer Webhook Parser Never Verifies the X-Mt-Signature HMAC — Unauthenticated Webhook Event Injection","details":"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.","published":"2026-07-14T18:56:20.615Z","modified":"2026-08-12T03:51:25.471140577Z","cvss":null,"epss":{"score":0.00238,"percentile":0.15179,"asOf":"2026-08-20"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Packagist","name":"symfony/mailtrap-mailer","fixedVersion":"7.4.12"},{"ecosystem":"Packagist","name":"symfony/mailtrap-mailer","fixedVersion":"8.0.12"},{"ecosystem":"Packagist","name":"symfony/symfony","fixedVersion":"7.4.12"},{"ecosystem":"Packagist","name":"symfony/symfony","fixedVersion":"8.0.12"}],"fix":{"url":"https://github.com/symfony/symfony/commit/4e0467e4e182cf2e704a3d9e1bc1a6be65d52ab8","label":"symfony/symfony@4e0467e"},"references":[{"type":"WEB","url":"https://github.com/symfony/symfony/releases/tag/v7.4.12"},{"type":"WEB","url":"https://github.com/symfony/symfony/releases/tag/v8.0.12"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/45xxx/CVE-2026-45755.json"},{"type":"ADVISORY","url":"https://github.com/symfony/symfony/security/advisories/GHSA-59f3-vp2f-mp9w"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-45755"},{"type":"FIX","url":"https://github.com/symfony/symfony/commit/4e0467e4e182cf2e704a3d9e1bc1a6be65d52ab8"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:25.471140577Z"}}