CVE-2024-51481

Nix allows macOS sandbox escape via built-in builders

Published Oct 31, 2024 CVSS 4.0 · 1 Low EPSS < 1% KEV · Not listed
Description
Nix is a package manager for Linux and other Unix systems. On macOS, built-in builders (such as `builtin:fetchurl`, exposed to users with `import <nix/fetchurl.nix>`) were not executed in the macOS sandbox. Thus, these builders (which are running under the `nixbld*` users) had read access to world-readable paths and write access to world-writable paths outside of the sandbox. This issue is fixed in 2.18.9, 2.19.7, 2.20.9, 2.21.5, 2.22.4, 2.23.4, and 2.24.10. Note that sandboxing is not enabled by default on macOS. The Nix sandbox is not primarily intended as a security mechanism, but as an aid to improve reproducibility and purity of Nix builds. However, sandboxing *can* mitigate the impact of other security issues by limiting what parts of the host system a build has access to.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
EUVD EUVD EUVD-2024-45355 Nix is a package manager for Linux and other Unix systems. On macOS, built-in builders (such as `builtin:fetchurl`, exposed to users with `import <nix/fetchurl.nix>`) were not executed in the macOS sandbox. Thus, these builders (which are running under the `nixbld*` users) had read access to world-readable paths and write access to world-writable paths outside of the sandbox. This issue is fixed in 2.18.9, 2.19.7, 2.20.9, 2.21.5, 2.22.4, 2.23.4, and 2.24.10. Note that sandboxing is not enabled by default on macOS. The Nix sandbox is not primarily intended as a security mechanism, but as an aid to improve reproducibility and purity of Nix builds. However, sandboxing *can* mitigate the impact of other security issues by limiting what parts of the host system a build has access to.
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description Nix is a package manager for Linux and other Unix systems. On macOS, built-in builders (such as `builtin:fetchurl`, exposed to users with `import <nix/fetchurl.nix>`) were not executed in the macOS sandbox. Thus, these builders (which are running under the `nixbld*` users) had read access to world-readable paths and write access to world-writable paths outside of the sandbox. This issue is fixed in 2.18.9, 2.19.7, 2.20.9, 2.21.5, 2.22.4, 2.23.4, and 2.24.10. Note that sandboxing is not enabled by default on macOS. The Nix sandbox is not primarily intended as a security mechanism, but as an aid to improve reproducibility and purity of Nix builds. However, sandboxing *can* mitigate the impact of other security issues by limiting what parts of the host system a build has access to.
Title Nix allows macOS sandbox escape via built-in builders
Weaknesses CWE-693
References
Metrics cvssV4_0

{'score': 1, 'vector': 'CVSS:4.0/AV:L/AC:H/AT:P/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Oct 31, 2024, 4:51 PM
Reserved
Oct 28, 2024, 2:20 PM
Status
Deferred
Published
Oct 31, 2024, 5:15 PM
Modified
Jun 17, 2026, 8:05 AM