CVE-2025-48934

Deno.env.toObject() ignores the variables listed in --deny-env and returns all environment variables

MEDIUM
5.3
CVSS Score
Published: June 4, 2025 at 07:21 PM UTC
Updated: June 17, 2026 at 09:30 AM UTC
2 products affected across 2 vendorsDenoDeno

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Severity
MEDIUM5.3
Exploit prediction
EPSS 0.4%
SSVC
PoC

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

95%
v < 2.1.132.2.0 ≤ v < 2.2.13
Affected range stops below 2.1.13, so it looks safe — our inference, not a vendor statement
Affected range stops below 2.2.13, so it looks safe — our inference, not a vendor statement
v < 2.1.13v < 2.2.13
Affected range stops below 2.1.13, so it looks safe — our inference, not a vendor statement
Affected range stops below 2.2.13, so it looks safe — our inference, not a vendor statement

SSVC — Action Prioritization

SSVCPoCAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
LOW
Integrity
NONE
Availability
NONE
Vector?

Quick Info

StatusANALYZED
CWE
CWE-201

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