{"id":47069,"date":"2026-04-14T17:34:50","date_gmt":"2026-04-14T17:34:50","guid":{"rendered":"http:\/\/localhost\/?p=47069"},"modified":"2026-04-14T17:34:50","modified_gmt":"2026-04-14T17:34:50","slug":"chamilo-lms-idor-in-apicourserelusers-allows-unauthorized-enrollment-of-arbitrary-users-into-courses","status":"publish","type":"post","link":"https:\/\/zero.redgem.net\/?p=47069","title":{"rendered":"Chamilo LMS: IDOR in \/api\/course_rel_users Allows Unauthorized Enrollment of Arbitrary Users into Courses_CVE-2026-34602"},"content":{"rendered":"<p>{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;Chamilo LMS is an open-source learning management system. In versions prior to 2.0.0-RC.3, the \/api\/course_rel_users endpoint is vulnerable to Insecure Direct Object Reference (IDOR), allowing an authenticated attacker to modify the user parameter in the request body to enroll any arbitrary user into any course without proper authorization checks. The backend trusts the user-supplied input for the user field and performs no server-side verification that the requester owns the referenced user ID or has permission to act on behalf of other users. This enables unauthorized manipulation of user-course relationships, potentially granting unintended access to course materials, bypassing enrollment controls, and compromising platform integrity. This issue has been fixed in version  2.0.0-RC.3.&#8221;,&#8221;published&#8221;:&#8221;2026-04-14T21:29:06.585Z&#8221;,&#8221;modified&#8221;:&#8221;2026-04-14T21:29:06.585Z&#8221;,&#8221;type&#8221;:&#8221;cve&#8221;,&#8221;title&#8221;:&#8221;Chamilo LMS: IDOR in \/api\/course_rel_users Allows Unauthorized Enrollment of Arbitrary Users into Courses&#8221;,&#8221;source&#8221;:&#8221;GitHub_M&#8221;,&#8221;references&#8221;:&#8221;https:\/\/github.com\/chamilo\/chamilo-lms\/security\/advisories\/GHSA-x373-8j9j-g5pj\\nhttps:\/\/github.com\/chamilo\/chamilo-lms\/commit\/2a9f060fa9d50fc9a92ed93af774d2619642df92\\nhttps:\/\/github.com\/chamilo\/chamilo-lms\/commit\/bd2ba34c2e74475587e38c74c90c2934e69c8779\\nhttps:\/\/github.com\/chamilo\/chamilo-lms\/commit\/c9c30cdc48afae57cd6ab012ae2eceafd351a40e\\nhttps:\/\/github.com\/chamilo\/chamilo-lms\/releases\/tag\/v2.0.0-RC.3&#8243;,&#8221;id&#8221;:&#8221;CVE-2026-34602&#8243;,&#8221;bulletinFamily&#8221;:&#8221;&#8221;,&#8221;cwe&#8221;:[&#8220;CWE-639&#8243;],&#8221;cvelist&#8221;:null,&#8221;sourceData&#8221;:&#8221;chamilo chamilo-lms \\u003c 2.0.0-RC.3&#8243;,&#8221;sourceHref&#8221;:&#8221;&#8221;,&#8221;cvss&#8221;:{&#8220;score&#8221;:7.1,&#8221;severity&#8221;:&#8221;HIGH&#8221;,&#8221;vector&#8221;:&#8221;CVSS:3.1\/AV:N\/AC:L\/PR:L\/UI:N\/S:U\/C:L\/I:H\/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;chamilo-lms&#8221;,&#8221;version&#8221;:&#8221;\\u003c 2.0.0-RC.3&#8243;,&#8221;vendor&#8221;:&#8221;chamilo&#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;Chamilo LMS is an open-source learning management system. In versions prior to 2.0.0-RC.3, the \/api\/course_rel_users endpoint is vulnerable to Insecure Direct Object Reference (IDOR), allowing&#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":[6,8,50,12,15,13,7,11,5],"class_list":["post-47069","post","type-post","status-publish","format-standard","hentry","category-category_cve","tag-cve","tag-cvss","tag-cvss-71","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>Chamilo LMS: IDOR in \/api\/course_rel_users Allows Unauthorized Enrollment of Arbitrary Users into Courses_CVE-2026-34602 - 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=47069\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Chamilo LMS: IDOR in \/api\/course_rel_users Allows Unauthorized Enrollment of Arbitrary Users into Courses_CVE-2026-34602 - zero redgem\" \/>\n<meta property=\"og:description\" content=\"{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;Chamilo LMS is an open-source learning management system. 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