> For the complete documentation index, see [llms.txt](https://hacking-notes.jord4n.pro/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://hacking-notes.jord4n.pro/hacking-wifi/wpa-wpa2-psk-network-attacks/precomputed-attacks/cowpatty-cracking-against-a-rainbow-table.md).
# Cowpatty Cracking Against a Rainbow Table
Use Cowpatty with a precomputed GenPMK database and captured handshake.
After creating a GenPMK database, Cowpatty can use it to check a captured handshake.
The database and capture must use the same network name. Here, the ESSID is `jordan`.
### Run the lookup
Use the precomputed `dic.genpmk` database with the capture:
{% code overflow="wrap" %}
```bash
cowpatty -d dic.genpmk -r Capture-01.cap -s jordan
```
{% endcode %}
The parameters are:
* `-d dic.genpmk` selects the GenPMK database.
* `-r Capture-01.cap` provides the captured handshake.
* `-s jordan` sets the target network name.
Cowpatty finds the password in less than 0.03 seconds. The lookup rate is 445,106 passwords per second.
Precomputed values make the lookup much faster. They avoid recalculating every candidate during this step.
---
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