{"id":"CVE-2026-93639","aliases":["EUVD-2026-108978","GHSA-q3fj-jg2r-pp4p"],"status":"published","title":"Zimbra Collaboration Suite Missing Authorization in ConfigureZimlet Enables Delegated Administrator Privilege Escalation","description":"A missing authorization vulnerability in Zimbra Collaboration Suite (ZCS) allows a delegated administrator with no explicit administrative grants to overwrite global Zimlet configuration through ConfigureZimletRequest. The uploaded configuration can also add an attacker-controlled domain to the proxy allowlist of the default class of service. If a signed-in user in that class opens a crafted /service/proxy URL, Zimbra serves attacker-controlled HTML under its own origin. The resulting JavaScript can read mailbox data and perform authenticated actions as the victim. Exploitation requires a delegated-administrator account and access to the admin SOAP service; the browser compromise additionally requires the victim to open the crafted URL. ZCS 10.1.16 and 10.1.20 are affected.","severity":{"version":"3.1","score":8.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.00375,"percentile":0.31882,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-862"],"published":"2026-10-23T13:29:25Z","modified":"2026-10-28T20:18:53Z","products":[{"vendor":"zimbra","product":"zimbra collaboration suite"}],"references":[{"url":"https://wiki.zimbra.com/wiki/Zimbra_Security_Advisories","tags":["vendor-advisory"]},{"url":"https://www.rapid7.com/blog/post/ve-breaking-zimbra-identity-boundaries-part-1/","tags":["related"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-93639"},{"url":"https://www.rapid7.com/blog/post/ve-breaking-zimbra-identity-boundaries-part-1"},{"url":"https://github.com/advisories/GHSA-q3fj-jg2r-pp4p"}],"sources":{"cve":[{"id":"CVE-2026-93639","title":"Zimbra Collaboration Suite Missing Authorization in ConfigureZimlet Enables Delegated Administrator Privilege Escalation","description":"A missing authorization vulnerability in Zimbra Collaboration Suite (ZCS) allows a delegated administrator with no explicit administrative grants to overwrite global Zimlet configuration through ConfigureZimletRequest. The uploaded configuration can also add an attacker-controlled domain to the proxy allowlist of the default class of service. If a signed-in user in that class opens a crafted /service/proxy URL, Zimbra serves attacker-controlled HTML under its own origin. The resulting JavaScript can read mailbox data and perform authenticated actions as the victim. Exploitation requires a delegated-administrator account and access to the admin SOAP service; the browser compromise additionally requires the victim to open the crafted URL. ZCS 10.1.16 and 10.1.20 are affected.","status":"published","published":"2026-10-23T13:29:25.939Z","modified":"2026-10-28T19:49:41.321Z","cvss":[{"version":"3.1","score":8.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N","level":"high","assessor":"cna"}],"cwes":["CWE-862"],"updated_at":"2026-11-02T14:19:54.50686Z"}],"euvd":[{"id":"EUVD-2026-108978","description":"A missing authorization vulnerability in Zimbra Collaboration Suite (ZCS) allows a delegated administrator with no explicit administrative grants to overwrite global Zimlet configuration through ConfigureZimletRequest. The uploaded configuration can also add an attacker-controlled domain to the proxy allowlist of the default class of service. If a signed-in user in that class opens a crafted /service/proxy URL, Zimbra serves attacker-controlled HTML under its own origin. The resulting JavaScript can read mailbox data and perform authenticated actions as the victim. Exploitation requires a delegated-administrator account and access to the admin SOAP service; the browser compromise additionally requires the victim to open the crafted URL. ZCS 10.1.16 and 10.1.20 are affected.","status":"published","published":"2026-10-23T13:29:25Z","modified":"2026-10-28T19:49:41Z","cvss":[{"version":"3.1","score":8.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N","level":"high"}],"updated_at":"2026-11-02T16:59:18.841799Z"}],"ghsa":[{"id":"GHSA-q3fj-jg2r-pp4p","title":"A missing authorization vulnerability in Zimbra Collaboration Suite (ZCS) allows a delegated...","description":"A missing authorization vulnerability in Zimbra Collaboration Suite (ZCS) allows a delegated administrator with no explicit administrative grants to overwrite global Zimlet configuration through ConfigureZimletRequest. The uploaded configuration can also add an attacker-controlled domain to the proxy allowlist of the default class of service. If a signed-in user in that class opens a crafted /service/proxy URL, Zimbra serves attacker-controlled HTML under its own origin. The resulting JavaScript can read mailbox data and perform authenticated actions as the victim. Exploitation requires a delegated-administrator account and access to the admin SOAP service; the browser compromise additionally requires the victim to open the crafted URL. ZCS 10.1.16 and 10.1.20 are affected.","status":"published","published":"2026-10-23T15:31:39Z","modified":"2026-10-23T15:31:51Z","cvss":[{"version":"3.1","score":8.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N","level":"high"}],"cwes":["CWE-862"],"updated_at":"2026-11-02T15:14:20.113334Z"}],"nvd":[{"id":"CVE-2026-93639","description":"A missing authorization vulnerability in Zimbra Collaboration Suite (ZCS) allows a delegated administrator with no explicit administrative grants to overwrite global Zimlet configuration through ConfigureZimletRequest. The uploaded configuration can also add an attacker-controlled domain to the proxy allowlist of the default class of service. If a signed-in user in that class opens a crafted /service/proxy URL, Zimbra serves attacker-controlled HTML under its own origin. The resulting JavaScript can read mailbox data and perform authenticated actions as the victim. Exploitation requires a delegated-administrator account and access to the admin SOAP service; the browser compromise additionally requires the victim to open the crafted URL. ZCS 10.1.16 and 10.1.20 are affected.","status":"published","published":"2026-10-23T14:17:57.64Z","modified":"2026-10-28T20:18:53.563Z","cvss":[{"version":"3.1","score":8.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N","level":"high","assessor":"secondary"}],"cwes":["CWE-862"],"updated_at":"2026-11-02T14:13:03.126833Z"}]}}