Bug 2520170

Summary: CVE-2026-11861 freeipa: FreeIPA: Obtaining TGS with impersonating cname through trust relationships [fedora-all]
Product: [Fedora] Fedora Reporter: Vladimir Vasilev <vvasilev>
Component: freeipaAssignee: IPA Maintainers <ipa-maint>
Status: CLOSED ERRATA QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: medium Docs Contact:
Priority: medium    
Version: rawhideCC: abokovoy, ftrivino, ipa-maint, mhjacks, rcritten, ssorce, twoerner
Target Milestone: ---Keywords: Security, SecurityTracking
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard: {"flaws": ["5d1a9ef0-b8f1-4664-8f49-0192e2b8c0bd"]}
Fixed In Version: freeipa-4.13.3-1.1.fc44 freeipa-4.13.3-1.1.fc43 Doc Type: ---
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2026-08-25 01:02:45 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On:    
Bug Blocks: 2487472    

Description Vladimir Vasilev 2026-08-20 10:04:58 UTC
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.

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.

Comment 1 Fedora Update System 2026-08-20 11:21:32 UTC
FEDORA-2026-903d904933 (freeipa-4.13.3-1.fc44 and samba-4.24.6-1.fc44) has been submitted as an update to Fedora 44.
https://bodhi.fedoraproject.org/updates/FEDORA-2026-903d904933

Comment 2 Fedora Update System 2026-08-21 05:41:06 UTC
FEDORA-2026-903d904933 has been pushed to the Fedora 44 testing repository.
Soon you'll be able to install the update with the following command:
`sudo dnf upgrade --enablerepo=updates-testing --refresh --advisory=FEDORA-2026-903d904933`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-903d904933

See also https://fedoraproject.org/wiki/QA:Updates_Testing for more information on how to test updates.

Comment 3 Fedora Update System 2026-08-21 09:48:50 UTC
FEDORA-2026-3a48220f1f (freeipa-4.13.3-1.1.fc43) has been submitted as an update to Fedora 43.
https://bodhi.fedoraproject.org/updates/FEDORA-2026-3a48220f1f

Comment 4 Fedora Update System 2026-08-22 01:39:36 UTC
FEDORA-2026-903d904933 has been pushed to the Fedora 44 testing repository.
Soon you'll be able to install the update with the following command:
`sudo dnf upgrade --enablerepo=updates-testing --refresh --advisory=FEDORA-2026-903d904933`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-903d904933

See also https://fedoraproject.org/wiki/QA:Updates_Testing for more information on how to test updates.

Comment 5 Fedora Update System 2026-08-22 02:21:13 UTC
FEDORA-2026-3a48220f1f has been pushed to the Fedora 43 testing repository.
Soon you'll be able to install the update with the following command:
`sudo dnf upgrade --enablerepo=updates-testing --refresh --advisory=FEDORA-2026-3a48220f1f`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-3a48220f1f

See also https://fedoraproject.org/wiki/QA:Updates_Testing for more information on how to test updates.

Comment 6 Fedora Update System 2026-08-25 01:02:45 UTC
FEDORA-2026-903d904933 (freeipa-4.13.3-1.1.fc44 and samba-4.24.6-1.fc44) has been pushed to the Fedora 44 stable repository.
If problem still persists, please make note of it in this bug report.

Comment 7 Fedora Update System 2026-09-04 01:26:32 UTC
FEDORA-2026-3a48220f1f (freeipa-4.13.3-1.1.fc43) has been pushed to the Fedora 43 stable repository.
If problem still persists, please make note of it in this bug report.