CVE-2026-114490

Incorrect Authorization in hMailServer

Published Oct 21, 2026 CVSS 3.1 · 7.8 High EPSS < 1% KEV · Not listed
Description
Incorrect authorization in the COM administration API of Progressive Robot hMailServer 6.3.4 through 6.3.6 allows an account assigned the serveradmin role with a list of domains - a credential an administrator may create meaning to confine it to those domains - to act as the whole-server administrator over COM. Administrator roles are meant to confine such a credential to the domains its list names, and the REST API did not take it for the server administrator, but the COM API's server-administrator check read the administer_server permission as the whole server whatever list the grant carried. So the credential signed in through the Control Panel, or through a script run on the server, as the server administrator of every domain: it could read and change every domain's accounts and mail, rename any domain, map a domain alias onto any, write the server's settings and secrets, and create further server-administrator accounts. The COM API's domain-administrator check, asked with no domain, likewise let an account assigned the domainadmin role with a list of domains that leaves out the account's own domain administer that domain's ordinary accounts over COM. An account holding serveradmin with no list is the server administrator by design and is unaffected, as are the help desk, auditor and custom roles.

Remediation

Vendor Solution

Upgrade to hMailServer 6.3.7, in which the one authorization rule answers administer_server only for a grant that reaches every domain, so an account assigned serveradmin with a list of domains is confined to the domains the list names, holding serveradmin's permissions in them short of what reaches beyond a domain and none in any other: over COM it is refused the server settings, a domain alias, a domain's name and the other changes that reach beyond a domain, exactly as over the REST API, where the same rule answers the check, and it is a domain administrator of its own account's domain where the list names that domain; it reaches the other domains its list names through REST, and over COM through the calls that name a domain of their own, among them the password reset, the unlock, the mailbox move and its history, the message trace, role assignment and a message's sender (send-as). An account assigned domainadmin with a list of domains likewise administers its own account's domain over COM only where the list names that domain. A grant with no list of domains is unchanged. Until then, do not assign the serveradmin role with a list of domains to a credential that must be confined: assign a custom role holding only the permissions it needs, with the list of domains, or the domainadmin role with a list of domains that names the account's own domain.

Tracking

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Advisories

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History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Progressive Robot
Progressive Robot hmailserver
Vendors & Products Progressive Robot
Progressive Robot hmailserver
Type Values Removed Values Added
Description Incorrect authorization in the COM administration API of Progressive Robot hMailServer 6.3.4 through 6.3.6 allows an account assigned the serveradmin role with a list of domains - a credential an administrator may create meaning to confine it to those domains - to act as the whole-server administrator over COM. Administrator roles are meant to confine such a credential to the domains its list names, and the REST API did not take it for the server administrator, but the COM API's server-administrator check read the administer_server permission as the whole server whatever list the grant carried. So the credential signed in through the Control Panel, or through a script run on the server, as the server administrator of every domain: it could read and change every domain's accounts and mail, rename any domain, map a domain alias onto any, write the server's settings and secrets, and create further server-administrator accounts. The COM API's domain-administrator check, asked with no domain, likewise let an account assigned the domainadmin role with a list of domains that leaves out the account's own domain administer that domain's ordinary accounts over COM. An account holding serveradmin with no list is the server administrator by design and is unaffected, as are the help desk, auditor and custom roles.
Title Incorrect Authorization in hMailServer
Weaknesses CWE-863
References
Metrics cvssV3_1

{'score': 7.8, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitLab
Published
Updated
Oct 29, 2026, 8:55 PM
Reserved
Oct 21, 2026, 3:34 PM
Status
Awaiting Analysis
Published
Oct 21, 2026, 4:17 PM
Modified
Oct 29, 2026, 9:17 PM