djust: WebSocket/runtime reconstructed request omits the client Host, causing host/subdomain TenantResolvers to misresolve the tenant on the live pathGHSA-v9rj-xjfv-xj9r
MEDIUMGHSA-v9rj-xjfv-xj9r is a medium-severity (CVSS 6.3) CWE-348 vulnerability in djust. A fix is available for djust — see the affected versions and patch details below.
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for GHSA-v9rj-xjfv-xj9r.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
djustReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
Description
djust provides Phoenix LiveView-style reactive server-side rendering for Django with Rust-powered performance. Prior to version 1.0.7, the WebSocket handle_mount and ViewRuntime._build_request rebuild an HttpRequest via RequestFactory().get(...) with no HTTP_HOST, so request.get_host() defaulted to "testserver" on the live path. Host/subdomain/domain TenantResolvers then misresolved the tenant — None on the live path while the HTTP path resolved correctly. With STRICT_MODE=False the tenant-scoped managers returned unscoped rows (cross-tenant disclosure); with the default they returned an empty queryset (broken tenancy). This is fixed in djust 1.0.7. The handshake Host is extracted from the ASGI scope, validated against ALLOWED_HOSTS (the same logic as the CSWSH Origin gate, parsed with Django's split_domain_port so malformed Hosts are rejected at the boundary), and propagated — with the TLS scheme — into the reconstructed request, so live-path tenant resolution matches HTTP exactly. There is no known workaround on the live path short of upgrading. Users are most exposed when combined with STRICT_MODE=False.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | djust | all versions | 1.0.7pip install --upgrade 'djust==1.0.7' |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for djust, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update djust to 1.0.7 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-v9rj-xjfv-xj9r is resolved across your whole dependency graph.
Workarounds
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.
Frequently Asked Questions
Is GHSA-v9rj-xjfv-xj9r in your dependencies?
Find it across PyPI, including transitive dependencies.