CyberSecBulletin
CVE-2026-61599NVD status: Deferred

djust: Use of Externally-Controlled Input to Select Classes or Code

Published Updated By the CyberSecBulletin desk

CVE-2026-61599 is a high-severity use of externally-controlled input to select classes or code vulnerability in djust from Djust-org, with a CVSS 4.0 base score of 8.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected djust versions: < 1.0.7. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.6% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of djust you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on github.com for workarounds and exact fixed builds.
  3. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
Djust-orgdjust< 1.0.7Not stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Attack requirements
NoneThe attack does not depend on a particular deployment or configuration.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Confidentiality (vulnerable system)
LowLimited loss of confidentiality on the vulnerable system.
Integrity (vulnerable system)
HighSerious loss of integrity on the vulnerable system.
Availability (vulnerable system)
LowLimited loss of availability on the vulnerable system.
Confidentiality (other systems)
NoneNo loss of confidentiality on systems beyond the vulnerable one.
Integrity (other systems)
NoneNo loss of integrity on systems beyond the vulnerable one.
Availability (other systems)
NoneNo loss of availability on systems beyond the vulnerable one.

Vector: 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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X. Scored by CNA (github.com).

Official description

djust provides Phoenix LiveView-style reactive server-side rendering for Django with Rust-powered performance. Prior to version 1.0.7, 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. Version 1.0.7 fixes the issue with 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`). As a workaround, 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.)

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Use of Externally-Controlled Input to Select Classes or Code

The product uses external input with reflection to select which classes or code to use, but it does not sufficiently prevent the input from selecting improper classes or code.

How developers prevent this class of flaw

  • Refactor your code to avoid using reflection.
  • Do not use user-controlled inputs to select and load classes or code.
  • Apply strict input validation by using allowlists or indirect selection to ensure that the user is only selecting allowable classes or code.

More Use of Externally-Controlled Input to Select Classes or Code vulnerabilities (CWE-470)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in djust

All djust vulnerabilities

Recent Use of Externally-Controlled Input to Select Classes or Code vulnerabilities

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