CVE-2023-22499

Workarounds

Run with --no-prompt flag to disable interactive permission prompts.

Multi-threaded programs were able to spoof interactive permission prompt by rewriting the prompt to suggest that program is waiting on user confirmation to unrelated action.

A malicious program could clear the terminal screen after permission prompt was shown and write a generic message like so:

// Expected prompt
⚠️  ┌ Deno requests read access to "./log.txt".
   ├ Requested by `Deno.open()` API
   ├ Run again with --allow-read to bypass this prompt.
   └ Allow? [y/n] (y = yes, allow; n = no, deny) >

// Prompt that users would see
Do you want to continue?

This situation impacts users who use Web Worker API and relied on interactive permission prompt. The reproduction is very timing sensitive and can’t be reliably reproduced on every try.

This problem can not be exploited on systems that do not attach an interactive prompt (for example headless servers).

Multiple concurrent operations access a shared resource without proper synchronization, producing unpredictable results depending on timing. Typical impact: TOCTOU exploits, data corruption, or privilege escalation.

CVE-2023-22499 has a CVSS score of 8.8 (High). The vector is network-reachable, no privileges required, and user interaction required. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (1.29.3); upgrading removes the vulnerable code path.

Kodem intelligence

The problem has been fixed in Deno v1.29.3; it is recommended all users update to this version.

1. What is CVE-2023-22499? CVE-2023-22499 is a high-severity race condition vulnerability in deno (rust), affecting versions >= 1.9.0, < 1.29.3. It is fixed in 1.29.3. Multiple concurrent operations access a shared resource without proper synchronization, producing unpredictable results depending on timing.
2. How severe is CVE-2023-22499? CVE-2023-22499 has a CVSS score of 8.8 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
3. Which versions of deno are affected by CVE-2023-22499? deno (rust) versions >= 1.9.0, < 1.29.3 is affected.
4. Is there a fix for CVE-2023-22499? Yes. CVE-2023-22499 is fixed in 1.29.3. Upgrade to this version or later.
5. Is CVE-2023-22499 exploitable, and should I be worried? Whether CVE-2023-22499 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
6. What actually determines whether CVE-2023-22499 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
7. How do I fix CVE-2023-22499? Upgrade deno to 1.29.3 or later.