{"id":52610,"date":"2026-05-08T16:59:34","date_gmt":"2026-05-08T16:59:34","guid":{"rendered":"https:\/\/zero.redgem.net\/?p=52610"},"modified":"2026-05-08T16:59:34","modified_gmt":"2026-05-08T16:59:34","slug":"plunk-sns-webhook-forgery","status":"publish","type":"post","link":"https:\/\/zero.redgem.net\/?p=52610","title":{"rendered":"Plunk: SNS webhook forgery_CVE-2026-42193"},"content":{"rendered":"<p>{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;Plunk is an open-source email platform built on top of AWS SES. Prior to version 0.9.0, the \/webhooks\/sns endpoint accepts Amazon SNS notification payloads from unauthenticated requests without verifying the SNS signature, certificate, or topic ARN, meaning anyone can forge a valid-looking webhook request. This allows an unauthenticated attacker to spoof SNS events to trigger workflow automations, unsubscribe contacts, manipulate email delivery metrics, and potentially exhaust billing credits. 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Prior to version 0.9.0, the \/webhooks\/sns endpoint accepts Amazon SNS notification payloads from&#8230;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[2],"tags":[9,6,8,10,12,13,7,11,5],"class_list":["post-52610","post","type-post","status-publish","format-standard","hentry","category-category_cve","tag-critical","tag-cve","tag-cvss","tag-cvss-91","tag-exploit","tag-news","tag-security","tag-tapic","tag-vulnerability"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.5 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>Plunk: SNS webhook forgery_CVE-2026-42193 - zero redgem<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/zero.redgem.net\/?p=52610\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Plunk: SNS webhook forgery_CVE-2026-42193 - zero redgem\" \/>\n<meta property=\"og:description\" content=\"{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;Plunk is an open-source email platform built on top of AWS SES. 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