mischard

nix-revenge

kalmarctf

Task: source and VM exposed a web panel that accepted arbitrary Nix expressions and a root rebuild helper using VERSION_SUFFIX. Solution: poison the pinned Nix source fixed-output derivation with Linux fd smuggling, then let root rebuild Nix from the corrupted store path and leak the copied flag.

$ ls tags/ techniques/
nixnixosfixed_output_derivationfd_smugglingsource_poisoningsetuid_helperscm_rightsweb_panel
fod_corruptionscm_rights_fd_smugglingsource_tree_poisoningprivileged_rebuild_poisoning
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