Introduction

Zynga is an American social game developer. The company was founded in April 2007 with headquarters in San Francisco, California, United States. The company has a mission to “connect the world through video games”.

The company has developed multiple well-known games including Farmville, Zynga Poker, Words With Friends, Mafia Wars and Empires & Allies amongst others.

Zynga acknowledged the breach in September 2019 – in total, the data breach contains 206,267,210 records including duplicates and 150,363,954 records without duplicates.

What data is at risk?

The leaked data includes usernames, email addresses, dates of some sort (presumably registration and last visit dates), phone numbers and passwords hashed with the SHA-1 algorithm.

Email addresses

50 of the most frequently used email domains on Zynga can be seen below:

#	Email Domain	Frequency
1	gmail.com	57,066,237
2	yahoo.com	31,705,551
3	hotmail.com	19,621,241
4	aol.com	6,208,662
5	zyngawf.com	3,385,626
6	comcast.net	2,007,109
7	hotmail.co.uk	1,833,752
8	icloud.com	1,742,705
9	live.com	1,646,972
10	msn.com	1,229,160
11	ymail.com	1,033,850
12	outlook.com	996,471
13	sbcglobal.net	943,419
14	me.com	805,438
15	att.net	708,214
16	verizon.net	665,298
17	aim.com	648,613
18	yahoo.co.uk	620,792
19	hotmail.fr	547,208
20	qq.com	500,120
21	cox.net	471,127
22	googlemail.com	426,282
23	rocketmail.com	409,631
24	bellsouth.net	398,100
25	live.co.uk	343,250
26	gmail.con	327,016
27	btinternet.com	298,615
28	bigpond.com	279,067
29	zynga.com	264,152
30	charter.net	241,341
31	yahoo.con	220,323
32	mail.com	213,373
33	web.de	212,789
34	mac.com	204,985
35	optonline.net	199,181
36	mail.ru	188,894
37	yahoo.com.au	187,014
38	live.com.au	180,759
39	hotmail.it	169,146
40	gmx.de	162,993
41	yahoo.ca	162,234
42	yahoo.fr	162,115
43	sky.com	157,304
44	Gmail.com	147,545
45	naver.com	141,011
46	live.fr	125,987
47	earthlink.net	122,485
48	163.com	118,299
49	libero.it	115,875
50	orange.fr	114,819

From the list above we can make assumptions about the locations of Zynga users:

#	Domain Purpose / Country	User count
1	Commercial / United States	129,250,910
2	Network Infrastructure	5,756,274
3	Great Britain	2,797,794
4	France	950,129
5	Germany	375,782
6	Russia	188,894
7	Australia	367,773
8	Italy	285,021
9	Canada	162,234

We can clearly see that the majority of Zynga’s user base is based in Western Europe. Judging from the country list Zynga had at least 133,821,870 users based in Western Europe – this number would consume about 64.88% of users if we compare it against records with duplicates and about 88.99% of users if we compare it against records without duplicates. Eastern Europe’s numbers are much smaller – in this case we can run analysis only on Russia – Russia would consume a mere 0.09% of the entire user base if compared with records including duplicates and 0.13% of the entire user base if compared with records without duplicates. Keep in mind that this number could be significantly higher if we would run the analysis on all email domains.

Zynga, counting on the database with duplicates included, had 115,318,761 users with the email length of equal or less than 20 characters and 98,540,978 users with the email length of more than 20 characters.

Zynga also stored passwords hashed and salted with the SHA1DASH algorithm, which, due to the design of the hash, is very difficult to crack.

Registration and last visit dates

Zynga also stored two types of dates – we can assume that they were dedicated for registration and last visit dates because all of the dates in the second field are at least a few days older than the first field.

Some of the registration dates can be seen below:

#	Registration year	User count
1	2008	8,899
2	2009	308,323
3	2010	8,049,512
4	2011	52,509,859
5	2012	45,864,542
6	2013	33,692,947
7	2014	19,797,958
8	2015	11,798,930
9	2016	11,919,813
10	2017	13,229,242
11	2018	9,906,177
12	2019	6,738,581

We can clearly see that Zynga started exploding in 2010 – 2011. Presumably because Zynga launched two notable games – FarmVille in 2009 and CityVille in December 2010. That would also explain how they acquired so many users in 2011.

We can also look at the months of registration:

#	Year and month of registration	User count
1	January 2011	1,527,898
2	February 2011	3,187,321
3	March 2011	4,811,707
4	April 2011	4,104,531
5	May 2011	3,840,462
6	June 2011	4,251,794
7	July 2011	3,595,167
8	August 2011	4,967,098
9	September 2011	4,969,558
10	October 2011	4,951,815
11	November 2011	4,845,633
12	December 2011	7,456,875
13	January 2012	8,609,520
14	February 2012	6,166,747
15	March 2012	5,616,319
16	April 2012	4,593,770
17	May 2012	3,425,387
18	June 2012	2,914,675
19	May 2012	2,739,815
20	August 2012	2,180,118
21	September 2012	1,960,474
22	October 2012	1,924,118
23	November 2012	2,350,473
24	December 2012	3,383,126
25	January 2013	3,050,625
26	February 2013	2,014,609
27	March 2013	2,964,007
28	April 2013	2,538,785
29	May 2013	5,155,247
30	June 2013	5,620,240
31	July 2013	3,644,162
32	August 2013	2,016,390
33	September 2013	1,595,458
34	October 2013	1,674,013
35	November 2013	1,491,949
36	December 2013	1,927,462
37	January 2014	2,266,956
38	February 2014	2,495,039
39	March 2014	1,526,042
40	April 2014	1,367,953
41	May 2014	1,393,584
42	October 2014	1,736,345
43	November 2014	2,645,285
44	December 2014	1,961,001
45	January 2015	1,649,743
46	January 2016	1,690,730
47	May 2017	1,755,937
48	November 2017	1,841,061
49	December 2017	1,332,390
50	January 2018	1,319,939

Now we can take a glance at the last visit dates. First, lets break them down by year:

#	Year	User count
1	2013	58,687,929
2	2014	68,633,963
3	2015	14,879,156
4	2016	11,867,841
5	2017	22,641,704
6	2018	16,827,914
7	2019	20,286,276

We can clearly see that the vast majority of users last visit dates were in 2014 – Zynga’s first quarter results for 2014 showed that daily active user numbers fell from 53 million to 28 million year-over-year, so we can make an assumption that this was a pretty devastating year for Zynga.

Now we can also take a look at the last visit dates including months:

#	Year and month	User count
1	December 2013	58,631,283
2	January 2014	1,233,821
3	February 2014	1,910,625
4	March 2014	12,286,336
5	May 2014	1,286,521
6	June 2014	31,170,789
7	July 2014	1,102,223
8	August 2014	6,064,564
9	September 2014	2,637,421
10	October 2014	2,982,078
11	November 2014	4,074,683
12	December 2014	2,882,402
13	January 2015	2,343,310
14	February 2015	1,519,108
15	March 2015	1,158,878
16	October 2015	1,246,491
17	November 2015	1,212,826
18	December 2015	1,508,320
19	January 2016	1,955,831
20	February 2016	1,447,082
21	March 2016	1,148,311
22	April 2016	1,146,150
23	May 2016	1,227,472
24	February 2017	2,808,792
25	March 2017	2,224,243
26	April 2017	1,705,594
27	May 2017	2,191,226
28	June 2017	3,090,247
29	July 2017	1,960,363
30	August 2017	1,284,560
31	October 2017	1,740,587
32	November 2017	2,426,871
33	December 2017	1,729,112
34	June 2018	1,743,764
35	February 2018	1,183,800
36	March 2018	1,132,668
37	May 2018	1,394,505
38	June 2018	1,634,963
39	July 2018	1,455,900
40	August 2018	1,379,390
41	September 2018	1,409,367
42	October 2018	1,608,628
43	November 2018	1,441,809
44	December 2018	1,489,667
45	January 2019	1,678,076
46	February 2019	1,479,820
47	March 2019	1,850,556
48	April 2019	1,720,382
49	July 2019	3,792,126
50	August 2019	6,817,538

Phone numbers

Alongside email addresses, registration and last visit dates, Zynga also stored phone numbers allowing us to glance at the country calling codes to make further assumptions where Zynga users were based:

#	Country calling code	User count	Country
1	3	164,903,318	Unknown
2	33	101,870,140	France
3	333	35,302,909	France
4	334	54,502,673	United States (Alabama)
5	335	1,937,399	United States (Alabama)
6	336	3,791,932	United States (North Carolina)
7	337	2,815,516	United States (Louisiana)
8	338	1,980,136	United States (Kansas)
9	339	1,539,575	United States (Massachusetts)
10	34	9,679,368	Spain
11	340	1,096,303	United States (Virgin Islands)
12	343	1,644,088	Canada
13	344	1,545,168	United States (Maryland)
14	35	1,232,958	Unknown
15	36	26,450,768	Hungary
16	360	1,225,829	United States (Washington)
17	361	1,286,462	United States (Texas)
18	362	1,916,541	United States (Kansas)
19	363	4,450,702	United States (Missouri)
20	364	5,034,853	United States (Kentucky)
21	365	3,738,655	Canada
22	366	2,105,035	United States (North Carolina)
23	367	1,726,155	Canada
24	368	1,838,625	United States (Louisiana)
25	369	3,127,911	United States (California)
26	37	12,907,096	Discontinued, once was assigned to East Germany
27	370	2,669,477	Lithuania
28	371	2,535,843	Latvia
29	372	1,402,870	Estonia
30	373	1,186,081	Moldova
31	38	10,729,895	Ukraine
32	382	1,441,145	Montenegro
33	383	2,060,581	Kosovo
34	384	1,806,749	United States (Kansas)
35	39	2,033,093	Italy
36	7	48,921,308	Russia
37	70	3,084,166	United Kingdom
38	71	8,316,024	Botswana
39	716	1,030,008	United States (New York)
40	717	1,255,644	United States (Pennsylvania)
41	718	1,358,479	United States (New York, excluding Manhattan)
42	719	1,313,189	United States (Colorado)
43	72	14,019,502	Serbia
44	720	1,459,595	United States (Colorado)
45	721	1,323,153	United States (Saint Martin)
46	724	1,356,205	United States (Pennsylvania)
47	725	1,357,354	United States (Nevada)
48	726	1,191,305	United States (Texas)
49	727	1,611,795	United States (Florida)
50	728	2,053,585	United States (Virginia)
51	729	1,777,324	United States (Colorado)
52	73	10,745,346	Kazakhstan
53	730	1,698,551	United States (Illinois)
54	731	1,291,637	United States (Tennessee)
55	732	1,681,681	United States (New Jersey)
56	733	2,054,451	United States (Illinois)
57	734	1,495,079	United States (Michigan)
58	74	10,492,013	United Kingdom
59	740	1,013,513	United States (Ohio)
50	743	1,193,652	United States (North Carolina)
61	744	1,000,773	United States (Massachusetts)
62	745	1,151,327	United States (Florida)
63	746	1,422,644	United States (New York)
64	748	1,316,537	United States (New York)
65	75	1,564,523	Afghanistan
66	76	699,734	Norway

We can see that the most prevalent area code was “3” – it had over 164 million records, so the best guess here would be that this area code was assigned to another area too. We can also clearly see that there was a lot of numbers that were based in different states across the United States, so let’s dive into them too:

#	State	User count
1	Alabama	56,440,072
2	North Carolina	7,090,619
3	Kansas	5,703,426‬
4	New York	5,127,668
5	Kentucky	5,034,853
6	Louisiana	4,654,141
7	Colorado	4,550,108
8	Missouri	4,450,702
9	Illinois	3,753,002
10	California	3,127,911
11	Florida	2,763,122‬
12	Pennsylvania	2,611,849‬
13	Massachusetts	2,540,348
14	Texas	2,477,767
15	Virginia	2,053,585
16	New Jersey	1,681,681
17	Maryland	1,545,168
18	Michigan	1,495,079
29	Nevada	1,357,354
20	Tennesee	1,291,637
21	Washington	1,225,829
22	Virgin Islands	1,096,303
23	Ohio	1,013,513

Judging from the analysis above, we can tell that over a quarter – 27.36% – of the entire user base were apparently from Alabama if we compare the number against a database with duplicates. If we compare the number against the database without duplicates, we would see that users from Alabama consume an enormously huge percentage – 37.54% – of the whole user base: that’s more than some of the states combined.

Now we can also take a look at the rest of the area codes – this time, excluding the United States. Do note that the “Unknown” in the column represents an unusually high amount of users – it’s probably a mix between some countries.

#	Country	User count
1	Unknown	166,136,276
2	France	137,173,049‬
3	Spain	9,679,368
4	Canada	7,108,898‬
5	Hungary	26,450,768
6	Discontinued, once was assigned to East Germany	12,907,096
7	Lithuania	2,669,477
8	Latvia	2,535,843
9	Estonia	1,402,870
10	Moldova	1,186,081
11	Ukraine	10,729,895
12	Montenegro	1,441,145
13	Kosovo	2,060,581
14	Italy	2,033,093
15	Russia	48,921,308
16	Botswana	8,316,024
17	Serbia	14,019,502
18	Kazakhstan	10,745,346
19	United Kingdom	13,576,179
20	Afghanistan	1,564,523
21	Norway	699,734

We can see that the vast majority of Zynga’s users came either from the United States or the Western part of Europe.

Summary

Judging by the entire analysis above, we can draw an assumption that monthly active users of Zynga combined (from the beginning until the time of the breach) were nearing a few billion mark which is very impressive given that the service had its peak sometime in between 2011 and 2013.

Although this data breach, with duplicates included, impacted over 200 million users, Zynga’s team had done a very good job protecting the data by hashing the passwords with SHA1 and salts. As already mentioned above, due to its design, this hash is resilient to cracking, so further damage was avoided.