CVE-2024-51481: 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...

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.

Metrics

CVSS 4.0

1/10

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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

EPSS Probability

0.17%

6.5th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-693

References

Timeline

Published: Oct 31, 2024
Last Modified: Jun 17, 2026
Status: Deferred

Frequently Asked Questions

What is CVE-2024-51481?

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.

How severe is CVE-2024-51481?

CVE-2024-51481 has a CVSS score of 1/10 (LOW severity). The EPSS model estimates a 0.17% probability of exploitation in the next 30 days.

How do I fix CVE-2024-51481?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.