Vulnerability Description
Deno is a JavaScript, TypeScript, and WebAssembly runtime. Prior to versions 2.1.13 and 2.2.13, the `Deno.env.toObject` method ignores any variables listed in the `--deny-env` option of the `deno run` command. When looking at the documentation of the `--deny-env` option this might lead to a false impression that variables listed in the option are impossible to read. Software relying on the combination of both flags to allow access to most environment variables except a few sensitive ones will be vulnerable to malicious code trying to steal secrets using the `Deno.env.toObject()` method. Versions 2.1.13 and 2.2.13 contains a patch.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Deno | Deno | < 2.1.13 |
Related Weaknesses (CWE)
References
- https://docs.deno.com/api/deno/~/Deno.Env.toObjectProduct
- https://docs.deno.com/runtime/fundamentals/security/#environment-variablesProduct
- https://github.com/denoland/deno/commit/2959e083912420988066a001c2b2d6732a1b562fPatch
- https://github.com/denoland/deno/commit/946ccda1aa19a00c478a5e6826b75053b050d753Patch
- https://github.com/denoland/deno/pull/29079Issue TrackingPatch
- https://github.com/denoland/deno/security/advisories/GHSA-7w8p-chxq-2789ExploitVendor Advisory
- https://github.com/denoland/deno/security/advisories/GHSA-7w8p-chxq-2789ExploitVendor Advisory
FAQ
What is CVE-2025-48934?
CVE-2025-48934 is a vulnerability with a CVSS score of 5.3 (MEDIUM). Deno is a JavaScript, TypeScript, and WebAssembly runtime. Prior to versions 2.1.13 and 2.2.13, the `Deno.env.toObject` method ignores any variables listed in the `--deny-env` option of the `deno run`...
How severe is CVE-2025-48934?
CVE-2025-48934 has been rated MEDIUM with a CVSS base score of 5.3/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2025-48934?
Check the references section above for vendor advisories and patch information. Affected products include: Deno Deno.