GHSA-39c8-xcwr-gqff
Fix: ash-project/ash_phoenix@b396e1aGHSA-39c8-xcwr-gqff is a CWE-863 vulnerability. O3 Security confirms whether GHSA-39c8-xcwr-gqff is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Broken access control in AshPhoenix SubdomainHook via a nil tenant in handle_subdomain
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.
Detection & mitigation playbook
VulnerabilityDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for the affected component. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Remediation status
No patched version of the affected component has shipped for GHSA-39c8-xcwr-gqff yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.
Mitigate without a patch
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-39c8-xcwr-gqff is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-39c8-xcwr-gqff. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-39c8-xcwr-gqff in your dependencies?
O3 detects GHSA-39c8-xcwr-gqff across dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.