CVE Catalog

CVE-2026-44028

High
Published: Translated: NVD NIST

Summary

An issue was discovered in Nix before version 2.34.7 and Lix before version 2.95.2 related to unbounded recursion in the NAR parser, which could lead to a stack-to-heap overflow. If the parser is run on a coroutine stack, it may allow arbitrary code execution as the Nix daemon running with root privileges.

Risk Assessment

Organizations may face serious threats as all users with access to the daemon can exploit this vulnerability to execute malicious code. Potential consequences include system takeover and access to sensitive data.

Recommendation

It is recommended to update Nix to version 2.34.7 or newer and Lix to version 2.95.2 or newer to mitigate this vulnerability. Additionally, consider restricting daemon access to trusted users only.

Related vulnerabilities

Original NVD description (English source)

An issue was discovered in Nix before 2.34.7 and Lix before 2.95.2. Unbounded recursion in the NAR (Nix Archive) parser could lead to a stack-to-heap overflow when the parser is run on a coroutine stack. The stack is allocated without a guard page, which means that a stack overflow could overwrite memory on the heap and could allow arbitrary code execution as the Nix daemon (run as root in multi-user installations) if ASLR hardening is bypassed. This can be exploited by all users able to connect to the daemon (e.g., in Nix, this is configurable via the allowed-users setting, defaulting to all users). The fixed versions are 2.34.7, 2.33.6, 2.32.8, 2.31.5, 2.30.5, 2.29.4, and 2.28.7 for Nix (introduced in 2.24.4); and 2.95.2, 2.94.2, and 2.93.4 for Lix (introduced in 2.93.0).

Vulnerability data from NVD (NIST) · CISA KEV · EPSS