Hackvent 2019: Day 6

Challenge

HV19.H1 Hidden One

Francis Bacon was an English philosopher and statesman who served as Attorney General and as Lord Chancellor of England. His works are credited with developing the scientific method and remained influential through the scientific revolution. Bacon has been called the father of empiricism. His works argued for the possibility of scientific knowledge based only upon inductive reasoning and careful observation of events in nature. Most importantly, he argued science could be achieved by use of a sceptical and methodical approach whereby scientists aim to avoid misleading themselves. Although his practical ideas about such a method, the Baconian method, did not have a long-lasting influence, the general idea of the importance and possibility of a sceptical methodology makes Bacon the father of the scientific method. This method was a new rhetorical and theoretical framework for science, the practical details of which are still central in debates about science and methodology.

Bacon was the first recipient of the Queen's counsel designation, which was conferred in 1597 when Elizabeth I of England reserved Bacon as her legal advisor. After the accession of James VI and I in 1603, Bacon was knighted. He was later created Baron Verulam in 1618 and Viscount St. Alban in 1621. Because he had no heirs, both titles became extinct upon his death in 1626, at 65 years. Bacon died of pneumonia, with one account by John Aubrey stating that he had contracted the condition while studying the effects of freezing on the preservation of meat. He is buried at St Michael's Church, St Albans, Hertfordshire.

Born: January 22	     	 	   	   	 	       	     	  	  
Died: April 9   	  	 	    	  	      	   		  	  
Mother: Lady Anne   		 	   	   	      	  	      	  
Father: Sir Nicholas	 	      		    	    	  	  	      	      
Secrets: unknown

Solution

We notice there is italic text embedded within our first paragraph. As it turns out Francis Bacon devised a cipher called the Bacon cipher. Thus, we know we must transform the above text into a bacon code which can be deciphered. Each character that is stylised with italics will be converted to a B and every other character will be converted to an A. For efficiency, we use a python script to do this:

#!/usr/bin/env python

import re

str = '<em>F</em>ra<em>n</em>cis Baco<em>n</em> <em>w</em>a<em>s</em> <em>a</em>n E<em>ng</em>lish ph<em>i</em>l<em>os</em>o<em>p</em>her a<em>n</em>d <em>s</em>tat<em>e</em>sm<em>a</em>n w<em>h</em>o se<em>rve</em>d <em>a</em>s At<em>t</em>or<em>n</em>ey Gen<em>e</em>ral and as <em>L</em>or<em>d</em> <em>Ch</em>an<em>ce</em>l<em>l</em>or of <em>En</em>g<em>l</em>an<em>d</em>. Hi<em>s</em> <em>w</em>orks ar<em>e</em> c<em>red</em>it<em>e</em>d w<em>ith</em> d<em>e</em>ve<em>lo</em>pi<em>ng</em> <em>t</em>h<em>e</em> sci<em>e</em>nt<em>i</em>fic me<em>t</em>hod and re<em>m</em>ai<em>ned</em> in<em>fl</em>u<em>en</em>ti<em>al</em> th<em>rou</em>gh <em>t</em>he s<em>cien</em>tific <em>r</em>ev<em>o</em>l<em>u</em>ti<em>o</em>n.<em>B</em>a<em>co</em>n h<em>as</em> <em>b</em>e<em>e</em>n ca<em>l</em>led <em>th</em>e <em>f</em>ath<em>e</em>r o<em>f</em> emp<em>iric</em>i<em>s</em>m. <em>Hi</em>s <em>wor</em>ks ar<em>g</em>ued for th<em>e</em> po<em>ssi</em>bi<em>li</em>t<em>y</em> of s<em>c</em>ie<em>n</em>tifi<em>c</em> <em>kno</em>wl<em>edg</em>e b<em>a</em>se<em>d</em> onl<em>y</em> u<em>p</em>on i<em>n</em>du<em>c</em>t<em>i</em>ve <em>r</em>ea<em>s</em>onin<em>g</em> <em>a</em>nd c<em>aref</em>u<em>l</em> o<em>bs</em>er<em>v</em>ation o<em>f</em> <em>e</em>v<em>e</em>nt<em>s</em> in <em>na</em>tur<em>e</em>. Mo<em>st</em> <em>i</em>mp<em>ort</em>an<em>t</em>l<em>y</em>, <em>he</em> a<em>rgue</em>d sc<em>i</em>en<em>c</em>e co<em>uld</em> <em>b</em>e <em>a</em>c<em>hi</em>eved by us<em>e</em> of a <em>s</em>ce<em>p</em>t<em>ical</em> a<em>nd</em> me<em>t</em>hod<em>i</em>ca<em>l</em> <em>a</em>pp<em>roa</em>ch wh<em>er</em>eby <em>s</em>cientist<em>s</em> ai<em>m</em> t<em>o</em> avo<em>i</em>d m<em>i</em>sl<em>ead</em>in<em>g</em> themsel<em>ve</em>s. <em>A</em>lth<em>oug</em>h <em>h</em>is <em>p</em>ra<em>c</em>tic<em>a</em>l i<em>d</em>e<em>a</em>s ab<em>out</em> <em>s</em>u<em>ch</em> <em>a</em> <em>m</em>et<em>h</em>od, <em>t</em>he B<em>a</em>con<em>i</em>an meth<em>o</em>d, d<em>i</em>d no<em>t</em> have <em>a</em> l<em>o</em>n<em>g</em>-<em>la</em>s<em>t</em>ing <em>i</em>nfluen<em>c</em>e, <em>th</em>e <em>g</em>e<em>ne</em>ral <em>i</em>dea <em>of</em> <em>t</em>he imp<em>o</em>rta<em>n</em>ce and pos<em>s</em>i<em>b</em>il<em>it</em>y o<em>f</em> a s<em>c</em>ept<em>i</em>cal'


def repl(m):
    return '1' * len(m.group(1))

# Replace italic text with 1 and non-italic text with 0
str = str.replace(' ', '').replace(',', '').replace('.', '').replace('-', '')
str = re.sub('<em>(.*?)</em>', repl, str)
str = re.sub ('[A-Za-z .,-]', '0', str)

# Print as A and B's for easy decipher
str = str.replace('1', 'B').replace('0', 'A')
print(str)

It is important to note that we strip out some non-alphanumeric characters such as ,.- as  the Bacon cipher does not allow them in its alphabet.
Running this script we get the following output:

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

We use an online Bacon Cipher tool to decipher the text and get:

SANTALIKESHISBACONBUTALSOTHISBACONTHEPASSWORDISHVXBACONCIPHERISSIMPLEBUTCOOLXREPLACEXWITHBRACKETSANDUSEUPPERCASEFORALLCHARACTER

Which can be read as:

SANTA LIKES HIS BACON BUT ALSO THIS BACON THE PASSWORD IS 
HVXBACONCIPHERISSIMPLEBUTCOOLX
REPLACE X WITH BRACKETS AND USE UPPER CASE FOR ALL CHARACTER

We follow these instructions, adding in the missing 19, to get our final flag!

Flag:

HV19{BACONCIPHERISSIMPLEBUTCOOL}

Bonus

This challenge also contained the solution to HV19.H1 Hidden One.