{"id":19971,"date":"2025-10-02T17:31:12","date_gmt":"2025-10-02T17:31:12","guid":{"rendered":"http:\/\/localhost\/?p=19971"},"modified":"2025-10-02T17:31:12","modified_gmt":"2025-10-02T17:31:12","slug":"unbounded-memory-allocation-in-stalwart-imap-parser","status":"publish","type":"post","link":"https:\/\/zero.redgem.net\/?p=19971","title":{"rendered":"Unbounded Memory Allocation in Stalwart IMAP parser_CVE-2025-61600"},"content":{"rendered":"<p>{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;Stalwart is a mail and collaboration server. Versions 0.13.3 and below contain an unbounded memory allocation vulnerability in the IMAP protocol parser which allows remote attackers to exhaust server memory, potentially triggering the system&#8217;s out-of-memory (OOM) killer and causing a denial of service. The CommandParser implementation enforces size limits on its dynamic buffer in most parsing states, but several state handlers omit these validation checks. This issue is fixed in version 0.13.4. A workaround for this issue is to implement rate limiting and connection monitoring at the network level, however this does not provide complete protection.&#8221;,&#8221;published&#8221;:&#8221;2025-10-02T21:30:52.203Z&#8221;,&#8221;modified&#8221;:&#8221;2025-10-02T21:30:52.203Z&#8221;,&#8221;type&#8221;:&#8221;cve&#8221;,&#8221;title&#8221;:&#8221;Unbounded Memory Allocation in Stalwart IMAP parser&#8221;,&#8221;source&#8221;:&#8221;GitHub_M&#8221;,&#8221;references&#8221;:&#8221;https:\/\/github.com\/stalwartlabs\/stalwart\/security\/advisories\/GHSA-8jqj-qj5p-v5rr\\nhttps:\/\/github.com\/stalwartlabs\/stalwart\/commit\/a8e631e881bded8128358732f18e02ca94a4e677\\nhttps:\/\/github.com\/stalwartlabs\/stalwart\/releases\/tag\/v0.13.4&#8243;,&#8221;id&#8221;:&#8221;CVE-2025-61600&#8243;,&#8221;bulletinFamily&#8221;:&#8221;&#8221;,&#8221;cwe&#8221;:[&#8220;CWE-400&#8243;,&#8221;CWE-789&#8243;],&#8221;cvelist&#8221;:null,&#8221;sourceData&#8221;:&#8221;stalwartlabs stalwart \\u003c 0.13.4&#8243;,&#8221;sourceHref&#8221;:&#8221;&#8221;,&#8221;cvss&#8221;:{&#8220;score&#8221;:7.5,&#8221;severity&#8221;:&#8221;HIGH&#8221;,&#8221;vector&#8221;:&#8221;CVSS:3.1\/AV:N\/AC:L\/PR:N\/UI:N\/S:U\/C:N\/I:N\/A:H&#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;stalwart&#8221;,&#8221;version&#8221;:&#8221;\\u003c 0.13.4&#8243;,&#8221;vendor&#8221;:&#8221;stalwartlabs&#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;Stalwart is a mail and collaboration server. Versions 0.13.3 and below contain an unbounded memory allocation vulnerability in the IMAP protocol parser which allows remote&#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":[6,8,16,12,15,13,7,11,5],"class_list":["post-19971","post","type-post","status-publish","format-standard","hentry","category-category_cve","tag-cve","tag-cvss","tag-cvss-75","tag-exploit","tag-high","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>Unbounded Memory Allocation in Stalwart IMAP parser_CVE-2025-61600 - 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=19971\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Unbounded Memory Allocation in Stalwart IMAP parser_CVE-2025-61600 - zero redgem\" \/>\n<meta property=\"og:description\" content=\"{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;Stalwart is a mail and collaboration server. Versions 0.13.3 and below contain an unbounded memory allocation vulnerability in the IMAP protocol parser which allows remote...\" \/>\n<meta property=\"og:url\" content=\"https:\/\/zero.redgem.net\/?p=19971\" \/>\n<meta property=\"og:site_name\" content=\"zero redgem\" \/>\n<meta property=\"article:published_time\" content=\"2025-10-02T17:31:12+00:00\" \/>\n<meta name=\"author\" content=\"invoker\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"invoker\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"1 minute\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\\\/\\\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\\\/\\\/zero.redgem.net\\\/?p=19971#article\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/zero.redgem.net\\\/?p=19971\"},\"author\":{\"name\":\"invoker\",\"@id\":\"https:\\\/\\\/zero.redgem.net\\\/#\\\/schema\\\/person\\\/fbfeae8dfad117ac08a7621bee1a1dca\"},\"headline\":\"Unbounded Memory Allocation in Stalwart IMAP parser_CVE-2025-61600\",\"datePublished\":\"2025-10-02T17:31:12+00:00\",\"mainEntityOfPage\":{\"@id\":\"https:\\\/\\\/zero.redgem.net\\\/?p=19971\"},\"wordCount\":254,\"commentCount\":0,\"publisher\":{\"@id\":\"https:\\\/\\\/zero.redgem.net\\\/#organization\"},\"keywords\":[\"CVE\",\"CVSS\",\"CVSS-7.5\",\"exploit\",\"HIGH\",\"news\",\"Security\",\"tapic\",\"Vulnerability\"],\"articleSection\":[\"category_cve\"],\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"CommentAction\",\"name\":\"Comment\",\"target\":[\"https:\\\/\\\/zero.redgem.net\\\/?p=19971#respond\"]}]},{\"@type\":\"WebPage\",\"@id\":\"https:\\\/\\\/zero.redgem.net\\\/?p=19971\",\"url\":\"https:\\\/\\\/zero.redgem.net\\\/?p=19971\",\"name\":\"Unbounded Memory Allocation in Stalwart IMAP parser_CVE-2025-61600 - zero redgem\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/zero.redgem.net\\\/#website\"},\"datePublished\":\"2025-10-02T17:31:12+00:00\",\"breadcrumb\":{\"@id\":\"https:\\\/\\\/zero.redgem.net\\\/?p=19971#breadcrumb\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\\\/\\\/zero.redgem.net\\\/?p=19971\"]}]},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\\\/\\\/zero.redgem.net\\\/?p=19971#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\\\/\\\/zero.redgem.net\\\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Unbounded Memory Allocation in Stalwart IMAP parser_CVE-2025-61600\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\\\/\\\/zero.redgem.net\\\/#website\",\"url\":\"https:\\\/\\\/zero.redgem.net\\\/\",\"name\":\"zero redgem\",\"description\":\"\",\"publisher\":{\"@id\":\"https:\\\/\\\/zero.redgem.net\\\/#organization\"},\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\\\/\\\/zero.redgem.net\\\/?s={search_term_string}\"},\"query-input\":{\"@type\":\"PropertyValueSpecification\",\"valueRequired\":true,\"valueName\":\"search_term_string\"}}],\"inLanguage\":\"en-US\"},{\"@type\":\"Organization\",\"@id\":\"https:\\\/\\\/zero.redgem.net\\\/#organization\",\"name\":\"zero redgem\",\"url\":\"https:\\\/\\\/zero.redgem.net\\\/\",\"logo\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\\\/\\\/zero.redgem.net\\\/#\\\/schema\\\/logo\\\/image\\\/\",\"url\":\"\",\"contentUrl\":\"\",\"width\":191,\"height\":188,\"caption\":\"zero redgem\"},\"image\":{\"@id\":\"https:\\\/\\\/zero.redgem.net\\\/#\\\/schema\\\/logo\\\/image\\\/\"}},{\"@type\":\"Person\",\"@id\":\"https:\\\/\\\/zero.redgem.net\\\/#\\\/schema\\\/person\\\/fbfeae8dfad117ac08a7621bee1a1dca\",\"name\":\"invoker\",\"image\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\\\/\\\/secure.gravatar.com\\\/avatar\\\/f17c01d7338e6932bcde121cf83569393df3374625d25afd62677cfb528f2e3e?s=96&d=mm&r=g\",\"url\":\"https:\\\/\\\/secure.gravatar.com\\\/avatar\\\/f17c01d7338e6932bcde121cf83569393df3374625d25afd62677cfb528f2e3e?s=96&d=mm&r=g\",\"contentUrl\":\"https:\\\/\\\/secure.gravatar.com\\\/avatar\\\/f17c01d7338e6932bcde121cf83569393df3374625d25afd62677cfb528f2e3e?s=96&d=mm&r=g\",\"caption\":\"invoker\"},\"sameAs\":[\"https:\\\/\\\/zero.redgem.net\"],\"url\":\"https:\\\/\\\/zero.redgem.net\\\/?author=1\"}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"Unbounded Memory Allocation in Stalwart IMAP parser_CVE-2025-61600 - zero redgem","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/zero.redgem.net\/?p=19971","og_locale":"en_US","og_type":"article","og_title":"Unbounded Memory Allocation in Stalwart IMAP parser_CVE-2025-61600 - zero redgem","og_description":"{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;Stalwart is a mail and collaboration server. Versions 0.13.3 and below contain an unbounded memory allocation vulnerability in the IMAP protocol parser which allows remote...","og_url":"https:\/\/zero.redgem.net\/?p=19971","og_site_name":"zero redgem","article_published_time":"2025-10-02T17:31:12+00:00","author":"invoker","twitter_card":"summary_large_image","twitter_misc":{"Written by":"invoker","Est. reading time":"1 minute"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"Article","@id":"https:\/\/zero.redgem.net\/?p=19971#article","isPartOf":{"@id":"https:\/\/zero.redgem.net\/?p=19971"},"author":{"name":"invoker","@id":"https:\/\/zero.redgem.net\/#\/schema\/person\/fbfeae8dfad117ac08a7621bee1a1dca"},"headline":"Unbounded Memory Allocation in Stalwart IMAP parser_CVE-2025-61600","datePublished":"2025-10-02T17:31:12+00:00","mainEntityOfPage":{"@id":"https:\/\/zero.redgem.net\/?p=19971"},"wordCount":254,"commentCount":0,"publisher":{"@id":"https:\/\/zero.redgem.net\/#organization"},"keywords":["CVE","CVSS","CVSS-7.5","exploit","HIGH","news","Security","tapic","Vulnerability"],"articleSection":["category_cve"],"inLanguage":"en-US","potentialAction":[{"@type":"CommentAction","name":"Comment","target":["https:\/\/zero.redgem.net\/?p=19971#respond"]}]},{"@type":"WebPage","@id":"https:\/\/zero.redgem.net\/?p=19971","url":"https:\/\/zero.redgem.net\/?p=19971","name":"Unbounded Memory Allocation in Stalwart IMAP parser_CVE-2025-61600 - zero redgem","isPartOf":{"@id":"https:\/\/zero.redgem.net\/#website"},"datePublished":"2025-10-02T17:31:12+00:00","breadcrumb":{"@id":"https:\/\/zero.redgem.net\/?p=19971#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/zero.redgem.net\/?p=19971"]}]},{"@type":"BreadcrumbList","@id":"https:\/\/zero.redgem.net\/?p=19971#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/zero.redgem.net\/"},{"@type":"ListItem","position":2,"name":"Unbounded Memory Allocation in Stalwart IMAP parser_CVE-2025-61600"}]},{"@type":"WebSite","@id":"https:\/\/zero.redgem.net\/#website","url":"https:\/\/zero.redgem.net\/","name":"zero redgem","description":"","publisher":{"@id":"https:\/\/zero.redgem.net\/#organization"},"potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/zero.redgem.net\/?s={search_term_string}"},"query-input":{"@type":"PropertyValueSpecification","valueRequired":true,"valueName":"search_term_string"}}],"inLanguage":"en-US"},{"@type":"Organization","@id":"https:\/\/zero.redgem.net\/#organization","name":"zero redgem","url":"https:\/\/zero.redgem.net\/","logo":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/zero.redgem.net\/#\/schema\/logo\/image\/","url":"","contentUrl":"","width":191,"height":188,"caption":"zero redgem"},"image":{"@id":"https:\/\/zero.redgem.net\/#\/schema\/logo\/image\/"}},{"@type":"Person","@id":"https:\/\/zero.redgem.net\/#\/schema\/person\/fbfeae8dfad117ac08a7621bee1a1dca","name":"invoker","image":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/secure.gravatar.com\/avatar\/f17c01d7338e6932bcde121cf83569393df3374625d25afd62677cfb528f2e3e?s=96&d=mm&r=g","url":"https:\/\/secure.gravatar.com\/avatar\/f17c01d7338e6932bcde121cf83569393df3374625d25afd62677cfb528f2e3e?s=96&d=mm&r=g","contentUrl":"https:\/\/secure.gravatar.com\/avatar\/f17c01d7338e6932bcde121cf83569393df3374625d25afd62677cfb528f2e3e?s=96&d=mm&r=g","caption":"invoker"},"sameAs":["https:\/\/zero.redgem.net"],"url":"https:\/\/zero.redgem.net\/?author=1"}]}},"_links":{"self":[{"href":"https:\/\/zero.redgem.net\/index.php?rest_route=\/wp\/v2\/posts\/19971","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/zero.redgem.net\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/zero.redgem.net\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/zero.redgem.net\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/zero.redgem.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=19971"}],"version-history":[{"count":0,"href":"https:\/\/zero.redgem.net\/index.php?rest_route=\/wp\/v2\/posts\/19971\/revisions"}],"wp:attachment":[{"href":"https:\/\/zero.redgem.net\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=19971"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/zero.redgem.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=19971"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/zero.redgem.net\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=19971"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}