{"id":43960,"date":"2026-04-12T03:19:15","date_gmt":"2026-04-12T03:19:15","guid":{"rendered":"http:\/\/localhost\/?p=43960"},"modified":"2026-04-12T03:19:15","modified_gmt":"2026-04-12T03:19:15","slug":"group-office-authenticated-remote-code-execution-via-php-insecure-deserialization-in-abstractsetting","status":"publish","type":"post","link":"https:\/\/zero.redgem.net\/?p=43960","title":{"rendered":"Group-Office: Authenticated Remote Code Execution via PHP Insecure Deserialization in `AbstractSettingsCollection`_CVE-2026-34838"},"content":{"rendered":"<p>{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;Group-Office is an enterprise customer relationship management and groupware tool. Prior to versions 6.8.156, 25.0.90, and 26.0.12, a vulnerability in the AbstractSettingsCollection model leads to insecure deserialization when these settings are loaded. By injecting a serialized FileCookieJar object into a setting string, an authenticated attacker can achieve Arbitrary File Write, leading directly to Remote Code Execution (RCE) on the server. This issue has been patched in versions 6.8.156, 25.0.90, and 26.0.12.&#8221;,&#8221;published&#8221;:&#8221;2026-04-02T19:15:40.591Z&#8221;,&#8221;modified&#8221;:&#8221;2026-04-03T12:55:48.631Z&#8221;,&#8221;type&#8221;:&#8221;cve&#8221;,&#8221;title&#8221;:&#8221;Group-Office: Authenticated Remote Code Execution via PHP Insecure Deserialization in `AbstractSettingsCollection`&#8221;,&#8221;source&#8221;:&#8221;GitHub_M&#8221;,&#8221;references&#8221;:&#8221;https:\/\/github.com\/Intermesh\/groupoffice\/security\/advisories\/GHSA-h22j-frrf-5vxq\\nhttps:\/\/github.com\/Intermesh\/groupoffice\/releases\/tag\/v25.0.90\\nhttps:\/\/github.com\/Intermesh\/groupoffice\/releases\/tag\/v26.0.12\\nhttps:\/\/github.com\/Intermesh\/groupoffice\/releases\/tag\/v6.8.156&#8243;,&#8221;id&#8221;:&#8221;CVE-2026-34838&#8243;,&#8221;bulletinFamily&#8221;:&#8221;&#8221;,&#8221;cwe&#8221;:[&#8220;CWE-502&#8243;],&#8221;cvelist&#8221;:null,&#8221;sourceData&#8221;:&#8221;Intermesh groupoffice \\u003c 6.8.156\\nIntermesh groupoffice \\u003c 25.0.90\\nIntermesh groupoffice \\u003c 26.0.12&#8243;,&#8221;sourceHref&#8221;:&#8221;&#8221;,&#8221;cvss&#8221;:{&#8220;score&#8221;:10,&#8221;severity&#8221;:&#8221;CRITICAL&#8221;,&#8221;vector&#8221;:&#8221;CVSS:3.1\/AV:N\/AC:L\/PR:L\/UI:N\/S:C\/C:H\/I:H\/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;groupoffice&#8221;,&#8221;version&#8221;:&#8221;\\u003c 6.8.156&#8243;,&#8221;vendor&#8221;:&#8221;Intermesh&#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;Group-Office is an enterprise customer relationship management and groupware tool. Prior to versions 6.8.156, 25.0.90, and 26.0.12, a vulnerability in the AbstractSettingsCollection model leads to&#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":[9,6,8,36,12,13,7,11,5],"class_list":["post-43960","post","type-post","status-publish","format-standard","hentry","category-category_cve","tag-critical","tag-cve","tag-cvss","tag-cvss-100","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>Group-Office: Authenticated Remote Code Execution via PHP Insecure Deserialization in `AbstractSettingsCollection`_CVE-2026-34838 - 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=43960\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Group-Office: Authenticated Remote Code Execution via PHP Insecure Deserialization in `AbstractSettingsCollection`_CVE-2026-34838 - zero redgem\" \/>\n<meta property=\"og:description\" content=\"{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;Group-Office is an enterprise customer relationship management and groupware tool. 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