CVE-2026-44028

Summary

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).

Affected Software

VendorProductVersion RangeStatus
NixOSNix2.24.4 < 2.28.7affected
NixOSNix2.29.0 < 2.29.4affected
NixOSNix2.30.0 < 2.30.5affected
NixOSNix2.31.0 < 2.31.5affected
NixOSNix2.32.0 < 2.32.8affected
NixOSNix2.33.0 < 2.33.6affected
NixOSNix2.34.0 < 2.34.7affected
Lix ProjectLix2.93.0 < 2.93.4affected
Lix ProjectLix2.94.0 < 2.94.2affected
Lix ProjectLix2.95.0 < 2.95.2affected

Weaknesses

  • CWE-674: CWE-674 Uncontrolled Recursion

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: total

References