A former Defence employee has been jailed for posting national secrets on 4chan.

4chan is the anonymous image-hosting hub that many describe as one of the worst places on the internet, while others consider it the heart of online culture.

In October 2012, 24-year-old Michael Scerba uploaded two pages of a Defence intelligence report to the website, along with a thumbnail graphic reading “Julian Assange is my hero”.

A former member of the Defence Signals Directorate noticed the post, and clicked through to find the pages of a “Five Eyes only” document; intended only for Australia's intelligence allies.

The post attracted 15 comments in the hour it was live on the site.

The court heard Mr Scerba had burned the sensitive images to a disk, which police found broken in a bin when they searched his home.

Justice Richard Refshauge acknowledged Scerba's early guilty plea and his clean record, as well as the fact that he was severely depressed at the time of the offence.

But the judge still emphasised the importance of general deterrence, saying the “clang of the prison gates” would serve as a warning to anyone else thinking of trading national security for internet points.

Scerba was given a three month sentence, and is expected to be released from prison in February 2016, at which time he will be subject to a two-year good behaviour bond.