What is CVE-2025-48934?

CVE-2025-48934 is a medium-severity vulnerability in Deno, classified under Insertion of Sensitive Information into Sent Data. CVSS score: 5.3/10. Published 2025-06-04.

How severe is CVE-2025-48934?

Medium severity. CVSS v3 base score is 5.3 out of 10.

Is CVE-2025-48934 known to be exploited?

1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Vulnerability in Deno

CVE-2025-48934

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.

Published 2025-06-04 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N.

EPSS exploit prediction

EPSS: 0.004 (34.4th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 34th percentile — 34.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: +0.000

Affected products

Deno
Denoland Deno — versions < 2.1.13, >= 2.2.0, < 2.2.13

Weakness classification (CWE)

CWE-201 — Insertion of Sensitive Information into Sent Data

Public proof-of-concept exploits

fkie-cad/nvd-json-data-feeds

References

github.com/denoland/deno/security/advisories/GHSA-7w8p-chxq-2789 (Exploit, Vendor Advisory)
github.com/denoland/deno/pull/29079 (Patch, Issue Tracking)
github.com/denoland/deno/commit/2959e083912420988066a001c2b2d6732a1b562f (Patch)
github.com/denoland/deno/commit/946ccda1aa19a00c478a5e6826b75053b050d753 (Patch)
docs.deno.com/api/deno/~/Deno.Env.toObject (Product)
docs.deno.com/runtime/fundamentals/security/ (Product)

Frequently asked questions

What is CVE-2025-48934?: CVE-2025-48934 is a medium-severity vulnerability in Deno, classified under Insertion of Sensitive Information into Sent Data. CVSS score: 5.3/10. Published 2025-06-04.
How severe is CVE-2025-48934?: Medium severity. CVSS v3 base score is 5.3 out of 10.
Is CVE-2025-48934 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.