# gamelinux/passivedns

A network sniffer that logs all DNS server replies for use in a passive DNS setup

Repository: https://github.com/gamelinux/passivedns
Canonical: https://ross.abutalabs.com/products/passivedns
Homepage: http://gamelinux.org/
Language: C
License Family: other
Last push: 2024-05-28T06:32:17+00:00

## Health v2 (maintenance only)
Score: 32/100 (v2, computed 2026-09-02T17:46:02.011165+00:00)
- activity 0, release rhythm 35, longevity 100
- inputs: {"age_days": 5605, "days_push": 827, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: no_releases, no_license
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1734, forks 380 (observed 2026-08-28T04:05:29.035951+00:00)

## What it is
PassiveDNS is a network sniffer written in C that passively collects DNS server replies from a live interface or pcap files and logs them in a structured format. It caches and aggregates duplicate DNS answers in memory to reduce log volume while preserving DNS resolution history for security investigations.

## Use cases
- log all DNS server replies on a network interface
- extract DNS records from pcap files
- investigate domain and IP resolution history during incident response
- build a passive DNS database for network security monitoring
- trace malware C2 domains back to first-seen timestamps
- support digital forensics with historical DNS answer data

## When to choose
- you need historical DNS resolution data for incident handling or NSM
- you want a lightweight C-based sniffer that runs on a sensor or SPAN port
- you need to process pcap captures for DNS answers offline
- you want to deduplicate repetitive DNS answers without losing information

## When to avoid
- you need active DNS queries or a recursive resolver rather than passive collection
- you want a full NSM platform with a web UI and query interface rather than a log producer
- you need Windows-native packet capture support out of the box

## Facets
- artifact type: cli-tool
- maturity: maintenance
- function: networking, monitoring, security, logging, search-engine
- domain: security, networking, monitoring, developer-tools
- platform: cli, cross-platform
- tags: passive-dns, dns-sniffer, nsm, digital-forensics, incident-response, pcap, libpcap, linux

## Member repositories
- gamelinux/passivedns (main) score 32

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:05:29.035951+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T03:31:04.474701+00:00, confidence not recorded.
  - readme: https://github.com/gamelinux/passivedns (fetched 2026-08-28T04:05:29.035951+00:00, sha 52694f8994cf)
  - homepage: http://gamelinux.org/ (fetched 2026-08-29T11:08:03.983616+00:00, sha 1ae474da0c3e)
- Data as of 2026-08-30T08:39:29.467469+00:00.