SB20260423122 - Multiple vulnerabilities in Deno

Description

This security bulletin contains information about 2 vulnerabilities.

1) Improper access control (CVE-ID: CVE-2025-48888)

CWE-ID: CWE-284 - Improper Access Control

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear

The vulnerability allows a remote user to bypass read permission restrictions.

The vulnerability exists due to improper access control in the permission flag handling logic when processing combined --allow-read and --deny-read flags. A remote user can run code with this flag combination to bypass read permission restrictions.

This issue also affects other global unary permission flag combinations specified as --allow-* together with --deny-*.

2) Improper access control (CVE-ID: CVE-2025-48934)

CWE-ID: CWE-284 - Improper Access Control

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear

The vulnerability allows a remote user to disclose sensitive information.

The vulnerability exists due to improper access control in Deno.env.toObject() when enumerating environment variables under a --deny-env restriction. A remote user can execute malicious code that calls Deno.env.toObject() to disclose sensitive information.

The issue affects programs that rely on --allow-env together with --deny-env to block access to selected environment variables.

Remediation

Install update from vendor's website.

References

• https://github.com/denoland/deno/security/advisories/GHSA-xqxc-x6p3-w683
• https://github.com/advisories/GHSA-xqxc-x6p3-w683
• https://github.com/denoland/deno/security/advisories/GHSA-7w8p-chxq-2789