GCVE Workshop - 22 September 2026 (14:00-18:00), Luxembourg Before The Vulnopticon Conference - Registration

GHSA-7PRP-2623-8G45

Vulnerability from github – Published: 2026-09-16 22:09 – Updated: 2026-09-16 22:09
VLAI
Summary
djust has an unauthenticated arbitrary module import via the WebSocket/SSE view-mount path
Details

Impact

The djust live transport resolves the LiveView to mount from a client-supplied dotted path by calling __import__(module_path, ...). The module is imported — running its top-level code (import side effects)before the framework checks that the resolved object is a LiveView subclass and before any per-view authentication. The LIVEVIEW_ALLOWED_MODULES allowlist that should contain this is fail-open (if allowed_modules: — skipped when the setting is unset, the framework default) and uses loose startswith matching.

An unauthenticated WebSocket client (the WS handshake does not require auth; per-view auth runs only after import + instantiate) can therefore send a mount / live_redirect_mount / url_change frame (or an SSE mount) with view = "<any.importable.module>.AnyName" and cause the server to import — and execute the top-level code of — any importable Python module by name.

Consequences: server-side execution of arbitrary importable modules' import-time side effects by an unauthenticated client (effectively RCE-by-proxy on any host that has a side-effectful importable module), denial of service (import bombs / expensive dependency trees), and a module/class enumeration oracle via distinct error strings.

Reproduced end-to-end: an unauthenticated WebsocketCommunicator mount frame with the allowlist unset imported and executed a sentinel non-LiveView module before the "not a LiveView subclass" rejection.

Affected code

  • python/djust/websocket.py handle_mount (__import__ of the client view)
  • python/djust/runtime.py ViewRuntime.dispatch_mount / _instantiate_view (SSE + url_change path)
  • python/djust/sse.py SSE mount

Threat-model entry T4 (docs/audits/websocket-auth-2026-06.md) previously noted the default-open allowlist but understated the impact as mere LiveView-class probing; the real primitive is arbitrary-module import + top-level code execution, independent of whether the target is a LiveView.

Patches

Fixed by a fail-closed resolution gate (djust._view_resolution.is_view_import_allowed): a client view path resolves only if (a) its module is already loaded (sys.modules — so resolving runs no new code; URL-routed views loaded by URLconf at startup keep working with zero config) or (b) it matches LIVEVIEW_ALLOWED_MODULES on a module-segment boundary (explicit opt-in for lazily-imported views). The gate runs before __import__ at all three sinks (+ defense-in-depth inside _instantiate_view).

Workarounds

Set LIVEVIEW_ALLOWED_MODULES to the narrow list of modules that contain your mountable LiveView classes. (Note: pre-patch the allowlist is startswith-matched and the import still precedes the subclass check, so this is mitigation, not a complete fix.)

References

Reproducer + finding writeup retained privately by the maintainer.

Show details on source website

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "djust"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.0.7"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-61599"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-470"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-09-16T22:09:38Z",
    "nvd_published_at": null,
    "severity": "HIGH"
  },
  "details": "### Impact\nThe djust live transport resolves the LiveView to mount from a **client-supplied dotted path** by calling `__import__(module_path, ...)`. The module is imported \u2014 running its **top-level code (import side effects)** \u2014 *before* the framework checks that the resolved object is a `LiveView` subclass and *before* any per-view authentication. The `LIVEVIEW_ALLOWED_MODULES` allowlist that should contain this is **fail-open** (`if allowed_modules:` \u2014 skipped when the setting is unset, the framework default) and uses loose `startswith` matching.\n\nAn **unauthenticated** WebSocket client (the WS handshake does not require auth; per-view auth runs only after import + instantiate) can therefore send a `mount` / `live_redirect_mount` / `url_change` frame (or an SSE mount) with `view = \"\u003cany.importable.module\u003e.AnyName\"` and cause the server to import \u2014 and execute the top-level code of \u2014 **any importable Python module by name**.\n\n**Consequences:** server-side execution of arbitrary importable modules\u0027 import-time side effects by an unauthenticated client (effectively RCE-by-proxy on any host that has a side-effectful importable module), denial of service (import bombs / expensive dependency trees), and a module/class **enumeration oracle** via distinct error strings.\n\nReproduced end-to-end: an unauthenticated `WebsocketCommunicator` `mount` frame with the allowlist unset imported and executed a sentinel non-LiveView module before the \"not a LiveView subclass\" rejection.\n\n### Affected code\n- `python/djust/websocket.py` `handle_mount` (`__import__` of the client `view`)\n- `python/djust/runtime.py` `ViewRuntime.dispatch_mount` / `_instantiate_view` (SSE + `url_change` path)\n- `python/djust/sse.py` SSE mount\n\nThreat-model entry T4 (`docs/audits/websocket-auth-2026-06.md`) previously noted the default-open allowlist but understated the impact as mere LiveView-class probing; the real primitive is arbitrary-module import + top-level code execution, independent of whether the target is a LiveView.\n\n### Patches\nFixed by a fail-**closed** resolution gate (`djust._view_resolution.is_view_import_allowed`): a client view path resolves only if (a) its module is **already loaded** (`sys.modules` \u2014 so resolving runs no new code; URL-routed views loaded by URLconf at startup keep working with zero config) or (b) it matches `LIVEVIEW_ALLOWED_MODULES` on a **module-segment boundary** (explicit opt-in for lazily-imported views). The gate runs **before** `__import__` at all three sinks (+ defense-in-depth inside `_instantiate_view`).\n\n### Workarounds\nSet `LIVEVIEW_ALLOWED_MODULES` to the narrow list of modules that contain your mountable LiveView classes. (Note: pre-patch the allowlist is `startswith`-matched and the import still precedes the subclass check, so this is mitigation, not a complete fix.)\n\n### References\nReproducer + finding writeup retained privately by the maintainer.",
  "id": "GHSA-7prp-2623-8g45",
  "modified": "2026-09-16T22:09:38Z",
  "published": "2026-09-16T22:09:38Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/djust-org/djust/security/advisories/GHSA-7prp-2623-8g45"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/djust-org/djust"
    },
    {
      "type": "WEB",
      "url": "https://github.com/djust-org/djust/releases/tag/v1.0.7"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:H/VA:L/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "djust has an unauthenticated arbitrary module import via the WebSocket/SSE view-mount path"
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.


Loading…

Loading…

Loading…

Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Loading…

Detection rules are retrieved from Rulezet.

Loading…

Loading…

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.


Loading…