{"id":"CVE-2026-45755","aliases":["DEBIAN-CVE-2026-45755","EUVD-2026-44361","GHSA-59f3-vp2f-mp9w","UBUNTU-CVE-2026-45755"],"status":"published","title":"Symfony: Mailtrap Mailer Webhook Parser Never Verifies the X-Mt-Signature HMAC — Unauthenticated Webhook Event Injection","description":"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.","severity":{"version":"4.0","score":6.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.00267,"percentile":0.19024,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-306","CWE-347"],"published":"2026-05-28T17:33:47Z","modified":"2026-10-28T02:31:01Z","fixes":[{"ecosystem":"Packagist","package":"symfony/mailtrap-mailer","fixed_in":["7.4.12","8.0.12"],"sources":["ghsa","osv"]},{"ecosystem":"Packagist","package":"symfony/symfony","fixed_in":["7.4.12","8.0.12"],"sources":["ghsa","osv"]},{"ecosystem":"Debian:14","package":"symfony","fixed_in":["7.4.12+dfsg-1"],"sources":["osv"]}],"affected":[{"source":"ghsa","ecosystem":"Packagist","package":"symfony/mailtrap-mailer","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"7.2.0"},{"fixed":"7.4.12"}]}]},{"source":"ghsa","ecosystem":"Packagist","package":"symfony/mailtrap-mailer","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"8.0.0"},{"fixed":"8.0.12"}]}]},{"source":"ghsa","ecosystem":"Packagist","package":"symfony/symfony","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"7.2.0"},{"fixed":"7.4.12"}]}]},{"source":"ghsa","ecosystem":"Packagist","package":"symfony/symfony","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"8.0.0"},{"fixed":"8.0.12"}]}]},{"source":"osv","ecosystem":"Debian:14","package":"symfony","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"7.4.12+dfsg-1"}]}],"versions":["6.4.21+dfsg-2","6.4.24+dfsg-1","6.4.25+dfsg-1","7.0.4+dfsg-1","7.0.5+dfsg-1","7.0.6+dfsg-1","7.0.7+dfsg-1","7.1.0~beta1+dfsg-1","7.1.0~rc1+dfsg-1","7.1.2+dfsg-1","7.1.3+dfsg-1","7.1.4+dfsg-1","7.1.5+dfsg-1","7.2.0~beta1+dfsg-1","7.2.0~beta2+dfsg-1","7.2.0~rc1+dfsg-1","7.2.1+dfsg-1","7.2.2+dfsg-1","7.2.3+dfsg-1","7.2.4+dfsg-1","7.2.5+dfsg-1","7.2.6-1","7.3.0+dfsg-1","7.3.0~beta1+dfsg-1","7.3.0~beta2+dfsg-1","7.3.0~rc1+dfsg-1","7.3.1+dfsg-1","7.3.2+dfsg-1","7.3.3+dfsg-1","7.3.4+dfsg-1","7.3.5-1","7.4.0+dfsg-1","7.4.0+dfsg-2","7.4.0~beta1-1","7.4.0~beta1-2","7.4.0~beta2+dfsg-1","7.4.0~beta2+dfsg-2","7.4.0~beta2+dfsg-3","7.4.0~rc1+dfsg-1","7.4.0~rc2+dfsg-1","7.4.0~rc3+dfsg-1","7.4.10+dfsg-1","7.4.2+dfsg-1","7.4.2+dfsg-2","7.4.3+dfsg-1","7.4.4+dfsg-1","7.4.5+dfsg-1","7.4.6+dfsg-1","7.4.6+dfsg-2","7.4.7+dfsg-1","7.4.8+dfsg-1","7.4.9+dfsg-1"]},{"source":"osv","ecosystem":"Packagist","package":"symfony/mailtrap-mailer","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"7.2.0"},{"fixed":"7.4.12"}]}],"versions":["v7.2.0","v7.3.0","v7.3.0-BETA1","v7.3.0-RC1","v7.4.0","v7.4.0-BETA1","v7.4.0-RC1"]},{"source":"osv","ecosystem":"Packagist","package":"symfony/mailtrap-mailer","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"8.0.0"},{"fixed":"8.0.12"}]}],"versions":["v8.0.0"]},{"source":"osv","ecosystem":"Packagist","package":"symfony/symfony","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"7.2.0"},{"fixed":"7.4.12"}]}],"versions":["v7.2.0","v7.2.1","v7.2.2","v7.2.3","v7.2.4","v7.2.5","v7.2.6","v7.2.7","v7.2.8","v7.2.9","v7.3.0","v7.3.0-BETA1","v7.3.0-BETA2","v7.3.0-RC1","v7.3.1","v7.3.10","v7.3.11","v7.3.2","v7.3.3","v7.3.4","v7.3.5","v7.3.6","v7.3.7","v7.3.8","v7.3.9","v7.4.0","v7.4.0-BETA1","v7.4.0-BETA2","v7.4.0-RC1","v7.4.0-RC2","v7.4.0-RC3","v7.4.1","v7.4.10","v7.4.11","v7.4.2","v7.4.3","v7.4.4","v7.4.5","v7.4.6","v7.4.7","v7.4.8","v7.4.9"]},{"source":"osv","ecosystem":"Packagist","package":"symfony/symfony","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"8.0.0"},{"fixed":"8.0.12"}]}],"versions":["v8.0.0","v8.0.1","v8.0.10","v8.0.11","v8.0.2","v8.0.3","v8.0.4","v8.0.5","v8.0.6","v8.0.7","v8.0.8","v8.0.9"]},{"source":"osv","ecosystem":"Ubuntu:16.04:LTS","package":"symfony","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.7.1+dfsg-1","2.7.5+dfsg-1","2.7.9+dfsg-1","2.7.9+dfsg-1ubuntu2","2.7.10-0ubuntu2"]},{"source":"osv","ecosystem":"Ubuntu:Pro:18.04:LTS","package":"symfony","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.8.7+dfsg-1.3ubuntu1","3.4.3+dfsg-1ubuntu4","3.4.6+dfsg-1","3.4.6+dfsg-1ubuntu0.1","3.4.6+dfsg-1ubuntu0.1+esm1","3.4.6+dfsg-1ubuntu0.1+esm2"]},{"source":"osv","ecosystem":"Ubuntu:Pro:20.04:LTS","package":"symfony","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.3.4+dfsg-1ubuntu1","4.3.8+dfsg-1ubuntu1","4.3.8+dfsg-1ubuntu1+esm1","4.3.8+dfsg-1ubuntu1+esm2"]},{"source":"osv","ecosystem":"Ubuntu:Pro:22.04:LTS","package":"symfony","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["5.2.6+dfsg-1ubuntu7","5.4.4+dfsg-1ubuntu8","5.4.4+dfsg-1ubuntu8+esm1"]},{"source":"osv","ecosystem":"Ubuntu:Pro:24.04:LTS","package":"symfony","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["5.4.23+dfsg-1ubuntu1","5.4.35+dfsg-3ubuntu1","6.4.5+dfsg-3ubuntu2","6.4.5+dfsg-3ubuntu3","6.4.5+dfsg-3ubuntu3+esm1"]},{"source":"osv","ecosystem":"Ubuntu:25.10","package":"symfony","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["6.4.18+dfsg-1ubuntu1","6.4.21+dfsg-2","6.4.21+dfsg-2ubuntu1","6.4.24+dfsg-1"]},{"source":"osv","ecosystem":"Ubuntu:26.10","package":"symfony","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["7.4.7+dfsg-1ubuntu1","7.4.9+dfsg-1ubuntu1","7.4.13+dfsg-2ubuntu1","7.4.14+dfsg-1ubuntu2","7.4.15+dfsg-2ubuntu2","7.4.16+dfsg-1ubuntu2"]},{"source":"osv","ecosystem":"Ubuntu:26.04:LTS","package":"symfony","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["6.4.24+dfsg-1","7.4.5+dfsg-1ubuntu1","7.4.6+dfsg-2ubuntu1","7.4.7+dfsg-1ubuntu1"]}],"products":[{"vendor":"/mailtrap-mailer","product":"mailtrap-mailer"},{"vendor":"sensiolabs","product":"symfony"},{"vendor":"symfony","product":"symfony"}],"references":[{"url":"https://github.com/symfony/symfony/security/advisories/GHSA-59f3-vp2f-mp9w","tags":["x_refsource_CONFIRM","Patch","Vendor Advisory","advisory","web"]},{"url":"https://github.com/symfony/symfony/commit/4e0467e4e182cf2e704a3d9e1bc1a6be65d52ab8","tags":["x_refsource_MISC","Patch","fix","web"]},{"url":"https://github.com/symfony/symfony/releases/tag/v7.4.12","tags":["x_refsource_MISC","Product","Release Notes","web"]},{"url":"https://github.com/symfony/symfony/releases/tag/v8.0.12","tags":["x_refsource_MISC","Product","Release Notes","web"]},{"url":"https://github.com/FriendsOfPHP/security-advisories/blob/master/symfony/mailtrap-mailer/CVE-2026-45755.yaml","tags":["web"]},{"url":"https://github.com/FriendsOfPHP/security-advisories/blob/master/symfony/symfony/CVE-2026-45755.yaml","tags":["web"]},{"url":"https://symfony.com/cve-2026-45755","tags":["web"]},{"url":"https://github.com/advisories/GHSA-59f3-vp2f-mp9w"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/45xxx/CVE-2026-45755.json","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-45755","tags":["advisory"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2026-45755","tags":["advisory"]},{"url":"https://github.com/symfony/symfony","tags":["package"]},{"url":"https://ubuntu.com/security/CVE-2026-45755","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-45755","tags":["report"]},{"url":"https://symfony.com/blog/cve-2026-45755-mailtrap-mailer-webhook-parser-never-verifies-the-x-mt-signature-hmac-unauthenticated-webhook-event-injection","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2026-45755","title":"Symfony: Mailtrap Mailer Webhook Parser Never Verifies the X-Mt-Signature HMAC — Unauthenticated Webhook Event Injection","description":"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.","status":"published","published":"2026-07-14T18:56:20.615Z","modified":"2026-07-14T19:46:25.21Z","cvss":[{"version":"4.0","score":6.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N","level":"medium","assessor":"cna"}],"cwes":["CWE-306","CWE-347"],"updated_at":"2026-11-02T13:46:32.755125Z"}],"euvd":[{"id":"EUVD-2026-44361","description":"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.","status":"published","published":"2026-07-14T18:56:20Z","modified":"2026-07-14T19:46:25Z","cvss":[{"version":"4.0","score":6.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N","level":"medium"}],"updated_at":"2026-11-02T18:19:58.805605Z"}],"ghsa":[{"id":"GHSA-59f3-vp2f-mp9w","title":"Symfony's Mailtrap Mailer Webhook Parser Never Verifies the X-Mt-Signature HMAC — Unauthenticated Webhook Event Injection","description":"### Description\n\nThe Mailtrap mailer bridge ships a webhook request parser used to authenticate and decode the event callbacks Mailtrap POSTs to an application's webhook endpoint. Its `doParse(Request $request, #[\\SensitiveParameter] string $secret)` method receives the configured webhook secret but never reads it; it decodes and returns the payload unconditionally, ignoring the `X-Mt-Signature` HMAC header Mailtrap sends with each request.\n\nAs a result, an application that wires up the Mailtrap webhook endpoint accepts **any** POST to that URL, even when a signing secret is configured (the recommended setup). An attacker who knows the endpoint exists can submit forged event payloads, fake delivery / bounce / open / click / spam events, leading to suppression-list corruption, delivery-metrics fraud, etc.\n\n### Resolution\n\n`MailtrapRequestParser::doParse()` now requires and verifies the `X-Mt-Signature` header, an HMAC-SHA256 of the raw request body keyed with the configured secret, before decoding the payload, using a constant-time comparison.\n\nWhen no secret is configured the behaviour is unchanged: signature verification remains opt-in, but it is now actually enforced once opted in.\n\nThe patch for this issue is available [here](https://github.com/symfony/symfony/commit/4e0467e4e182cf2e704a3d9e1bc1a6be65d52ab8) for branch 7.4.\n\n### Credits\n\nSymfony would like to thank Himanshu Anand for reporting the issue and Alexandre Daubois providing the fix.","status":"published","published":"2026-05-28T17:33:47Z","modified":"2026-05-28T17:33:48Z","cvss":[{"version":"4.0","score":6.6,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:U","level":"medium"}],"cwes":["CWE-306","CWE-347"],"updated_at":"2026-11-02T14:40:14.666177Z"}],"nvd":[{"id":"CVE-2026-45755","description":"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.","status":"published","published":"2026-07-14T19:17:07.907Z","modified":"2026-07-15T13:42:26.507Z","cvss":[{"version":"4.0","score":6.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"medium","assessor":"secondary"},{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"medium","assessor":"primary"}],"cwes":["CWE-306","CWE-347"],"updated_at":"2026-11-02T14:12:29.879716Z"}],"osv":[{"id":"CVE-2026-45755","title":"Symfony: Mailtrap Mailer Webhook Parser Never Verifies the X-Mt-Signature HMAC — Unauthenticated Webhook Event Injection","description":"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.","status":"published","published":"2026-07-14T18:56:20.615Z","modified":"2026-10-28T02:31:01.355414155Z","cvss":[{"version":"4.0","score":6.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N","level":"medium"}],"cwes":["CWE-306","CWE-347"],"updated_at":"2026-11-02T15:45:05.525666Z"},{"id":"DEBIAN-CVE-2026-45755","description":"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.","status":"published","published":"2026-07-14T19:17:07.907Z","modified":"2026-10-01T03:03:14.625369022Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T15:45:55.669088Z"},{"id":"GHSA-59f3-vp2f-mp9w","title":"Symfony's Mailtrap Mailer Webhook Parser Never Verifies the X-Mt-Signature HMAC — Unauthenticated Webhook Event Injection","description":"### Description\n\nThe Mailtrap mailer bridge ships a webhook request parser used to authenticate and decode the event callbacks Mailtrap POSTs to an application's webhook endpoint. Its `doParse(Request $request, #[\\SensitiveParameter] string $secret)` method receives the configured webhook secret but never reads it; it decodes and returns the payload unconditionally, ignoring the `X-Mt-Signature` HMAC header Mailtrap sends with each request.\n\nAs a result, an application that wires up the Mailtrap webhook endpoint accepts **any** POST to that URL, even when a signing secret is configured (the recommended setup). An attacker who knows the endpoint exists can submit forged event payloads, fake delivery / bounce / open / click / spam events, leading to suppression-list corruption, delivery-metrics fraud, etc.\n\n### Resolution\n\n`MailtrapRequestParser::doParse()` now requires and verifies the `X-Mt-Signature` header, an HMAC-SHA256 of the raw request body keyed with the configured secret, before decoding the payload, using a constant-time comparison.\n\nWhen no secret is configured the behaviour is unchanged: signature verification remains opt-in, but it is now actually enforced once opted in.\n\nThe patch for this issue is available [here](https://github.com/symfony/symfony/commit/4e0467e4e182cf2e704a3d9e1bc1a6be65d52ab8) for branch 7.4.\n\n### Credits\n\nSymfony would like to thank Himanshu Anand for reporting the issue and Alexandre Daubois providing the fix.","status":"published","published":"2026-05-28T17:33:47Z","modified":"2026-09-10T03:50:45.630958598Z","cvss":[{"version":"4.0","score":6.6,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:U","level":"medium"}],"cwes":["CWE-306","CWE-347"],"updated_at":"2026-11-02T15:46:38.213481Z"},{"id":"UBUNTU-CVE-2026-45755","description":"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.","status":"published","published":"2026-07-14T19:17:00Z","modified":"2026-10-17T12:55:37.267859425Z","cvss":[{"version":"4.0","score":6.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N","level":"medium"},{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T16:56:26.396868Z"}]}}