CVE-2026-82724

Broken access control in AshPhoenix SubdomainHook via a nil tenant in handle_subdomain

Published Aug 31, 2026 CVSS 4.0 · 7.6 High EPSS < 1% KEV · Not listed
Description
Incorrect Authorization vulnerability in ash-project ash_phoenix invokes the SubdomainHook authorization callback with a nil tenant, so tenant-scoped access checks never see the tenant they are meant to enforce.

AshPhoenix.LiveView.SubdomainHook.on_mount/4 attached a handle_params hook to assign the tenant and then immediately called handle_subdomain in the same on_mount. The tenant assign is only written when LiveView later runs handle_params, strictly after on_mount returns, so handle_subdomain read an unset assign and ran as apply(m, f, [socket, nil | a]). A consumer gate that halts when the user does not belong to the tenant instead evaluated nil, either crashing or taking a permissive branch, and it was never re-run once the real subdomain was assigned or on later navigations. The fix runs handle_subdomain inside the handle_params hook with the real tenant on every navigation.

This issue affects ash_phoenix: from 2.1.26 before 2.3.25.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description Incorrect Authorization vulnerability in ash-project ash_phoenix invokes the SubdomainHook authorization callback with a nil tenant, so tenant-scoped access checks never see the tenant they are meant to enforce. AshPhoenix.LiveView.SubdomainHook.on_mount/4 attached a handle_params hook to assign the tenant and then immediately called handle_subdomain in the same on_mount. The tenant assign is only written when LiveView later runs handle_params, strictly after on_mount returns, so handle_subdomain read an unset assign and ran as apply(m, f, [socket, nil | a]). A consumer gate that halts when the user does not belong to the tenant instead evaluated nil, either crashing or taking a permissive branch, and it was never re-run once the real subdomain was assigned or on later navigations. The fix runs handle_subdomain inside the handle_params hook with the real tenant on every navigation. This issue affects ash_phoenix: from 2.1.26 before 2.3.25.
Title Broken access control in AshPhoenix SubdomainHook via a nil tenant in handle_subdomain
First Time appeared Ash-project
Ash-project ash Phoenix
Weaknesses CWE-863
CPEs cpe:2.3:a:ash-project:ash_phoenix:*:*:*:*:*:*:*:*
Vendors & Products Ash-project
Ash-project ash Phoenix
References
Metrics cvssV4_0

{'score': 7.6, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
EEF
Published
Updated
Aug 31, 2026, 3:54 PM
Reserved
Aug 31, 2026, 12:59 AM
Status
Deferred
Published
Aug 31, 2026, 4:17 AM
Modified
Sep 1, 2026, 9:15 PM