CVE-2024-27936 is a high-severity (CVSS 8.8) CWE-150 vulnerability in deno. 1 public exploit reference exists, so weaponization risk is real. O3 Security confirms whether CVE-2024-27936 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Deno interactive permission prompt spoofing via improper ANSI stripping
Real-World Exposure
deno🦀deno_runtimeReal-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 with secure defaults. Starting in version 1.32.1 and prior to version 1.41.0 of the deno library, maliciously crafted permission request can show the spoofed permission prompt by inserting a broken ANSI escape sequence into the request contents. Deno is stripping any ANSI escape sequences from the permission prompt, but permissions given to the program are based on the contents that contain the ANSI escape sequences. Any Deno program can spoof the content of the interactive permission prompt by inserting a broken ANSI code, which allows a malicious Deno program to display the wrong file path or program name to the user. Version 1.41.0 of the deno library contains a patch for the issue.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🦀crates.io | deno | ≥ 1.32.1&&< 1.41.0 | 1.41.0 |
| 🦀crates.io | deno_runtime | ≥ 0.103.0&&< 0.147.0 | 0.147.0 |
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. 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 deno to 1.41.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-27936 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-2024-27936 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-2024-27936. 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-2024-27936 in your dependencies?
O3 detects CVE-2024-27936 across crates.io dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.