Bug 2487472 (CVE-2026-11861)

Summary: CVE-2026-11861 FreeIPA: idm: ipa: FreeIPA: Obtaining TGS with impersonating cname through trust relationships
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: abokovoy, frenaud, ftrivino, jrische, rhel-process-autobot, security-response-team, watson-tool-maintainers
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in FreeIPA. When a trust relationship is configured between FreeIPA and Active Directory, Active Directory users can bypass authentication for FreeIPA services, including the portal, SMB server, and LDAP directory. This is possible by impersonating a client name in the Ticket Granting Service (TGS) due to FreeIPA services not verifying Privilege Attribute Certificate (PAC) certificates. This vulnerability could allow an authenticated Active Directory user to escalate their privileges within the FreeIPA domain.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On: 2520170    
Bug Blocks:    
Deadline: 2026-08-30   

Description OSIDB Bzimport 2026-06-10 11:50:40 UTC
If trust relationship between FreeIPA and Active Directory is configured (established/created), AD users can bypass authentication of the FreeIPA portal, SMB server, LDAP directory and, presumably, any other GSSAPI services unauthorized, using impersonation in TGS, under certain conditions. In the worst case scenario a user could escalate their priveleges (permissions/rights) in FreeIPA domain. This is due to the fact that the portal, like other GSSAPI services, is not configured to verify PAC certificates and trusts the TGS cname field.