Undettered by the Government's warning that it would deal with those who threaten to attack Singapore's cyber infrastructure, a hacking enthusiast tested his skills on the Prime Minister's Office (PMO) website.
Mohammad Azhar Tahir, 28, was sentenced to two months' jail yesterday for entering unauthorised computer code into the site on Nov 7 last year.
But the jobless man's total jail term comes up to six months, after including punishment for related computer-misuse offences.
These included tapping onto a neighbour's wireless Internet service, and modifying social media and e-mail accounts belonging to Ah Boys To Men actor Muhammad Ridhwan Azman, 21.
Mohammad Azhar had targeted the PMO website after hearing about the warning, which had been issued by Prime Minister Lee Hsien Loong.
This came after someone claiming links with international "hacktivist" group Anonymous had threatened to hit Singapore's computer networks.
Instead of proper search terms, Mohammad Azhar entered HTML code into a Google search bar embedded in the PMO site.
This resulted in a modified page that referenced Anonymous.
Internet users who clicked on a link containing script for the page, which he posted on various social media websites, would see a Guy Fawkes mask and two messages instead of what the search results page would normally display.
The messages were "It's great to be Singaporean today" and "ANONYMOUS SG WAS HERE BIATCH".
Mohammad Azhar had pleaded guilty on Nov 11 to seven of 59 charges.
He committed the PMO website intrusions with a technique known as cross-site scripting, which was one of various methods he had picked up over several years out of interest.
His brother, Mohammad Asyiq Tahir, 22, was also dealt with yesterday for computer misuse.
The national serviceman was placed on 18 months' probation after pleading guilty to five of 11 offences.
These largely involved tampering with Muhammad Ridhwan's e-mail and social media accounts. None concerned the PMO website server.
For each of two counts of securing unauthorised access to the website server, Mohammad Azhar could have been jailed for up to three years and fined up to $10,000.
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