{"id":42143,"date":"2026-02-21T05:28:22","date_gmt":"2026-02-21T05:28:22","guid":{"rendered":"http:\/\/localhost\/?p=42143"},"modified":"2026-02-21T05:28:22","modified_gmt":"2026-02-21T05:28:22","slug":"lettermint-nodejs-sdk-leaks-email-properties-to-unintended-recipients-when-client-instance-is-reused","status":"publish","type":"post","link":"https:\/\/zero.redgem.net\/?p=42143","title":{"rendered":"Lettermint Node.js SDK leaks email properties to unintended recipients when client instance is reused_CVE-2026-27492"},"content":{"rendered":"<p>{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;Lettermint Node.js SDK is the official Node.js SDK for Lettermint. In versions 1.5.0 and below, email properties (such as to, subject, html, text, and attachments) are not reset between sends when a single client instance is reused across multiple .send() calls. This can cause properties from a previous send to leak into a subsequent one, potentially delivering content or recipient addresses to unintended parties. Applications sending emails to different recipients in sequence \u2014 such as transactional flows like password resets or notifications \u2014 are affected. This issue has been fixed in version 1.5.1.&#8221;,&#8221;published&#8221;:&#8221;2026-02-21T10:16:03.913Z&#8221;,&#8221;modified&#8221;:&#8221;2026-02-21T10:16:03.913Z&#8221;,&#8221;type&#8221;:&#8221;cve&#8221;,&#8221;title&#8221;:&#8221;Lettermint Node.js SDK leaks email properties to unintended recipients when client instance is reused&#8221;,&#8221;source&#8221;:&#8221;GitHub_M&#8221;,&#8221;references&#8221;:&#8221;https:\/\/github.com\/lettermint\/lettermint-node\/security\/advisories\/GHSA-49pc-8936-wvfp\\nhttps:\/\/github.com\/lettermint\/lettermint-node\/commit\/24a17acbc2429c5eb30391f9df3dc0ea7aaf4de1\\nhttps:\/\/github.com\/lettermint\/lettermint-node\/blob\/main\/CHANGELOG.md#151-2026-02-20&#8243;,&#8221;id&#8221;:&#8221;CVE-2026-27492&#8243;,&#8221;bulletinFamily&#8221;:&#8221;&#8221;,&#8221;cwe&#8221;:[&#8220;CWE-488&#8243;],&#8221;cvelist&#8221;:null,&#8221;sourceData&#8221;:&#8221;lettermint lettermint-node \\u003c 1.5.1&#8243;,&#8221;sourceHref&#8221;:&#8221;&#8221;,&#8221;cvss&#8221;:{&#8220;score&#8221;:4.7,&#8221;severity&#8221;:&#8221;MEDIUM&#8221;,&#8221;vector&#8221;:&#8221;CVSS:3.1\/AV:L\/AC:H\/PR:L\/UI:N\/S:U\/C:H\/I:N\/A:N&#8221;,&#8221;version&#8221;:&#8221;3.1&#8243;},&#8221;cvss2&#8243;:{},&#8221;cvss3&#8243;:{&#8220;version&#8221;:&#8221;&#8221;,&#8221;vectorString&#8221;:&#8221;&#8221;,&#8221;baseScore&#8221;:0,&#8221;baseSeverity&#8221;:&#8221;&#8221;,&#8221;attackVector&#8221;:&#8221;&#8221;,&#8221;attackComplexity&#8221;:&#8221;&#8221;,&#8221;privilegesRequired&#8221;:&#8221;&#8221;,&#8221;userInteraction&#8221;:&#8221;&#8221;,&#8221;scope&#8221;:&#8221;&#8221;,&#8221;confidentialityImpact&#8221;:&#8221;&#8221;,&#8221;integrityImpact&#8221;:&#8221;&#8221;,&#8221;availabilityImpact&#8221;:&#8221;&#8221;,&#8221;cvssV3&#8243;:{&#8220;version&#8221;:&#8221;&#8221;,&#8221;vectorString&#8221;:&#8221;&#8221;,&#8221;baseScore&#8221;:0,&#8221;baseSeverity&#8221;:&#8221;&#8221;,&#8221;attackVector&#8221;:&#8221;&#8221;,&#8221;attackComplexity&#8221;:&#8221;&#8221;,&#8221;privilegesRequired&#8221;:&#8221;&#8221;,&#8221;userInteraction&#8221;:&#8221;&#8221;,&#8221;scope&#8221;:&#8221;&#8221;,&#8221;confidentialityImpact&#8221;:&#8221;&#8221;,&#8221;integrityImpact&#8221;:&#8221;&#8221;,&#8221;availabilityImpact&#8221;:&#8221;&#8221;}},&#8221;href&#8221;:&#8221;&#8221;,&#8221;category_name&#8221;:&#8221;CVE&#8221;,&#8221;post_link&#8221;:&#8221;&#8221;,&#8221;product&#8221;:&#8221;lettermint-node&#8221;,&#8221;version&#8221;:&#8221;\\u003c 1.5.1&#8243;,&#8221;vendor&#8221;:&#8221;lettermint&#8221;,&#8221;ai_description&#8221;:&#8221;&#8221;,&#8221;ai_severity&#8221;:&#8221;&#8221;,&#8221;ai_vendor&#8221;:&#8221;&#8221;,&#8221;ai_product&#8221;:&#8221;&#8221;,&#8221;ai_version&#8221;:&#8221;&#8221;,&#8221;ai_score&#8221;:0}<\/p>\n","protected":false},"excerpt":{"rendered":"<p>{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;Lettermint Node.js SDK is the official Node.js SDK for Lettermint. In versions 1.5.0 and below, email properties (such as to, subject, html, text, and attachments)&#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":[6,8,137,12,21,13,7,11,5],"class_list":["post-42143","post","type-post","status-publish","format-standard","hentry","category-category_cve","tag-cve","tag-cvss","tag-cvss-47","tag-exploit","tag-medium","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>Lettermint Node.js SDK leaks email properties to unintended recipients when client instance is reused_CVE-2026-27492 - 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=42143\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Lettermint Node.js SDK leaks email properties to unintended recipients when client instance is reused_CVE-2026-27492 - zero redgem\" \/>\n<meta property=\"og:description\" content=\"{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;Lettermint Node.js SDK is the official Node.js SDK for Lettermint. 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