Violations to be penalized under the law include cyber-espionage, false publications, child pornography, computer-borne forgery, cyber-stalking and cyber-bullying among others, the statement said, without spelling out the penalties.
Following the President assent to the Bill, Kenyans took to social media to air their views.
WhatsApp group administrators who condone sharing of fake news or information meant to incite ethnic hatred are also marked for severe punishment. He has assented into law Cyber Crime Bill.
The clause may go against the principles of freedom of expression by attempting to criminalise people - mostly bloggers - who may knowingly or unknowingly publish false information.
The offence leads to a fine not exceeding twenty million or to imprisonment for a term not exceeding twenty five years, or to both. Statistics show that financial institutions lose over Ksh.10 billion annually to hackers.
The objective of the Bill is to "protect the confidentiality, integrity and availability of computer systems, programs and data", "prevent the unlawful use of computer systems", "facilitate the investigation and prosecution of cybercrimes", and "facilitate global co-operation on matters".
Offenders could be fined up to $50 000 or be jailed up to two years in prison, or both.
False information, spread on social media, played a significant part in last year's election. This Bill amends various provisions of the Public Trustee Act, bringing it into conformity with the Constitution.
National Assembly Speaker Justin Muturi presented the Bills and witnessed the signing alongside Deputy President William Ruto, Interior Cabinet Secretary Fred Matiang'i, National Assembly Majority Leader Aden Duale, Attorney General Paul Kihara Kariuki and Solicitor General Kennedy Ogeto.