CVE-2026-33872
Fix: revelrylabs/elixir-nodejs#105CVE-2026-33872 is a CWE-362 vulnerability in nodejs. O3 Security confirms whether CVE-2026-33872 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
elixir-nodejs has Cross-User Data Leakage or Information Disclosure due to Worker Protocol Race Condition
Real-World Exposure
nodejsReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Hex packages — download data is not available via public APIs for these ecosystems.
Description
elixir-nodejs provides an Elixir API for calling Node.js functions. A vulnerability in versions prior to 3.1.4 results in Cross-User Data Leakage or Information Disclosure due to a race condition in the worker protocol. The lack of request-response correlation creates a "stale response" vulnerability. Because the worker does not verify which request a response belongs to, it may return the next available data in the buffer to an unrelated caller. In high-throughput environments where the library processes sensitive user data (e.g., PII, authentication tokens, or private records), a timeout or high concurrent load can cause Data A (belonging to User A) to be returned to User B. This may lead to unauthorized information disclosure that is difficult to trace, as the application may not throw an error but instead provide "valid-looking" yet entirely incorrect and private data to the wrong session. The issue is fixed in v3.1.4.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 💧Hex | nodejs | all versions | 3.1.4 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for nodejs. 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.
Fix
Update nodejs to 3.1.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-33872 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.
How O3 protects you
O3 pinpoints whether CVE-2026-33872 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 CVE-2026-33872. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-33872 in your dependencies?
O3 detects CVE-2026-33872 across Hex dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.