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vulnix 1.4.0

Scans a Nix store for derivations that are affected by vulnerabilities.

Nix(OS) vulnerability scanner

This is a utility that validates a Nix store for any packages that are reachable from live paths and likely to be affected by vulnerabilities listed in the NVD.

It implements a CLI utility to inspect the current status and a monitoring integration for Sensu.

Example output:

Found 5 advisories for libxslt, pcre, perl, ... (and 2 more)





Theory of operation

vulnix pulls all published CVEs from NIST and caches them locally. It matches name and version of all derivations referenced from the command line against known CVE entries. A whitelist is used to filter out unwanted results.

System requirements

  • Depends on common Nix tools like nix-store. These are expected to be in $PATH.
  • Depends on being able to interact with the Nix store database (/nix/var/nix/db). This means that it must either run as the same user that owns the Nix store database or nix-daemon must be active.
  • Parses *.drv files directly. Tested with Nix 1.10 and 1.11.
  • It refuses to work without some locale environment settings. Try export LANG=C.UTF-8 if you see encoding errors.

Usage Example

  • What vulnerabilities are listed for my current system:

    vulnix --system
  • Check nix-build output together with its transitive closure:

    vulnix result/
  • Check all passed derivations, but don’t determine requisites:

    vulnix -R /nix/store/*.drv
  • JSON output for machine post-processing:

    vulnix --json result/


The whitelist file uses a sub-set of the YAML language to define rules which matches shall be ignored or in other words are declared to be trusted or in progress, hence the term whitelist. If the match is partial, e.G. there is a package which is affected by more than one vulnerability, but only one is whitelist, the match will still be printed except for the declared exception.


[TBD: the whitelist feature is being revamped at the moment]


To create a development environment, use a Python 3 virtualenv:

pyvenv-3.5 .
bin/pip install -e .\[test]

Run tests:



1.4.0 (2017-11-27)

  • Guesses applied CVE patches out of the patches derivation envVar (see nixpkgs #15660).

1.3.4 (2017-10-29)

  • Add ‘–no-requisites’ flag which stops vulnix from determining the transitive closure of derivations passed on the command line.
  • Provide structured JSON output with –json.
  • Remove whitelist from README as it is quite buggy right now.

1.3.3 (2017-10-16)

  • Fix return code bug (#28741).
  • Fix partial whitelisting of products where several vulnerable versions are present on the system at the same time (#24).
  • Improve error reporting for incorrectly formed whitelist rules.

1.3.2 (2017-10-06)

  • Minor: fix packaging issues.

1.3.1 (2017-10-06)

  • Security: Fix arbitrary code execution bug during derivation evaluation.

1.3.0 (2017-09-18)

  • .drv files may be specified directly on the command line.
  • Updated PyPI dependencies.
  • Document system requirements (#12).
  • Don’t leave large files in /tmp around.
  • Remove duplicate CVEs in output (#25).
  • Fix bug with reporting less than 3 vulnerabilities (#28).

1.2.2 (2017-01-28)

  • Packaging improvements: pin versions in, include NVDCVE test data in sdist.
  • Reduce NVDCVE fixture size. This cuts tests run time by more than 50%.

1.2.1 (2017-01-27)

  • Skip /nix/var/nix/gcroots/booted-system during system check.
  • Make output a bit easier to read by removing visual clutter.

1.2 (2016-12-22)

  • Improve CPU and memory usage: refactored the way we fetch, parse, store and process data. We now leverage ZODB as the storage for parsed data that is efficient to look up.

    On our test systems this caused memory usage to drop from > 1GiB to ~70MiB and a pure evaluation of existing data to around 7-10 seconds.

    This change requires a re-retrieval of all historic sources.

  • Improve unit test coverage with at least a smoke test for our new fetching procedure.

1.1.5 (2016-10-13)

  • Keep a reverse index: product name -> vulnerabilities to speed up scan process.
  • Mark ‘in progress’ vulnerabilities with an asterisk
  • The ‘-w’ switch accepts URLs, too
  • vulnix no longer scans /var/nix/var/gcroots/booted-system
  • only cached files are saved (archives are to be deleted)
  • added travis build: runs periodically against nixpkgs/master and updates requirements*.nix files in case of success

1.1.4 (2016-08-25)

  • Add src to PYTHONPATH so that tests run also on older NixOS versions (tested on 15.09).
  • Correct URL, add metadata.
  • Add nix to propagatedBuildInputs, as vulnix calls nix-store at runtime.

1.1.3 (2016-08-16)

  • Pin the Python version to 3.4 (Nix only)

1.1.2 (2016-08-15)

  • Add Nix expressions (Nix/NixOS) to

1.1.1 (2016-08-12)

  • Add VERSION to

1.1 (2016-08-11)

  • Scans the whole system (NixOS only), the current user environment, or a project-specific path (e.g., ./result). #1
  • Allow to specify site-specific whitelists in addition to the builtin default whitelist. #4
  • Fully repeatable install using default.nix. Thanks to Rok Garbas. #4
  • Cache pre-parsed NVD files for improved scanning speed. #2
  • Support multiple whitelists (repeat -w option). #3
  • Cache NVD files in ~/.cache/vulnix. #7
  • Document whitelist file format. #10
  • Fix Nix build on macOS. #11
File Type Py Version Uploaded on Size
vulnix-1.4.0.tar.gz (md5) Source 2017-11-27 33KB