CVE-2024-27933 is a high-severity (CVSS 8.2) CWE-863 vulnerability in deno. 1 public exploit reference exists, so weaponization risk is real. A fix is available for deno — see the affected versions and patch details below.
Deno arbitrary file descriptor close via `op_node_ipc_pipe()` leading to permission prompt bypass
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
- A successful exploit gives an attacker total control of the affected component, not partial access.
Exploitation and automatability from CISA’s SSVC triage for CVE-2024-27933.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2024-27933 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,166 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
denoReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects crates.io packages — download data is not available via public APIs for these ecosystems.
Description
Deno is a JavaScript, TypeScript, and WebAssembly runtime. In version 1.39.0, use of raw file descriptors in op_node_ipc_pipe() leads to premature close of arbitrary file descriptors, allowing standard input to be re-opened as a different resource resulting in permission prompt bypass. Node child_process IPC relies on the JS side to pass the raw IPC file descriptor to op_node_ipc_pipe(), which returns a IpcJsonStreamResource ID associated with the file descriptor. On closing the resource, the raw file descriptor is closed together.
Use of raw file descriptors in op_node_ipc_pipe() leads to premature close of arbitrary file descriptors. This allow standard input (fd 0) to be closed and re-opened for a different resource, which allows a silent permission prompt bypass. This is exploitable by an attacker controlling the code executed inside a Deno runtime to obtain arbitrary code execution on the host machine regardless of permissions.
This bug is known to be exploitable. There is a working exploit that achieves arbitrary code execution by bypassing prompts from zero permissions, additionally abusing the fact that Cache API lacks filesystem permission checks. The attack can be conducted silently as stderr can also be closed, suppressing all prompt outputs.
Version 1.39.1 fixes the bug.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🦀crates.io | deno | ≥ 1.39.0&&< 1.39.1 | 1.39.1cargo update -p deno --precise 1.39.1 |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for deno, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update deno to 1.39.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-27933 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 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2024-27933 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2024-27933. 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-2024-27933 in your dependencies?
O3 Security finds CVE-2024-27933 across crates.io dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.