Russian	O
APT29	O
hackers	O
'	O
stealthy	O
malware	O
undetected	O
for	O
years	O
By	O
Ionut	O
Ilascu	O
January	O
27	O
,	O
2022	O
09:23	O
AM	O
0	O
Cozy	O
Bear	O
Russian	O
hackers	O
camouflage	O
new	O
malware	O
as	O
legitimate	O
files	O
EXCLUSIVE	O
:	O
Hackers	O
associated	O
with	O
the	O
Russian	B-ORGANIZATION
Federation	B-ORGANIZATION
Foreign	B-ORGANIZATION
Intelligence	B-ORGANIZATION
Service	B-ORGANIZATION
(	O
SVR	B-ORGANIZATION
)	O
continued	O
their	O
incursions	O
on	O
networks	O
of	O
multiple	O
organizations	O
after	B-CLASSIFICATION
the	O
SolarWinds	B-ORGANIZATION
supply	O
-	O
chain	O
compromise	O
using	O
two	O
recently	O
discovered	O
sophisticated	O
threats	O
.	O
The	O
malicious	O
implants	O
are	O
a	O
variant	O
of	O
the	O
GoldMax	O
backdoor	O
for	O
Linux	O
systems	O
and	O
a	O
completely	O
new	O
malware	O
family	O
that	O
cybersecurity	O
company	O
CrowdStrike	O
now	O
tracks	O
as	O
TrailBlazer	O
.	O
Both	O
threats	O
have	O
been	O
used	O
in	O
StellarParticle	O
campaigns	O
since	O
at	O
least	O
mid-2019	O
but	O
were	O
identified	O
only	O
two	O
years	O
later	O
,	O
during	O
incident	O
response	O
investigations	O
.	O
StellarParticle	O
attacks	O
have	O
been	O
attributed	O
to	O
the	O
APT29	B-THREAT_ACTOR
hacking	O
group	O
has	O
been	O
running	O
cyber	O
espionage	O
campaigns	O
for	O
more	O
than	O
12	O
years	O
and	O
is	O
also	O
known	O
as	O
CozyBear	B-THREAT_ACTOR
,	O
The	O
Dukes	O
,	O
and	O
Yttrium	O
.	O
Stealing	O
cookies	O
for	O
MFA	O
bypass	O
In	O
a	O
report	O
shared	O
exclusively	O
with	O
BleepingComputer	B-ORGANIZATION
,	O
cybersecurity	O
company	O
CrowdStrike	O
today	O
describes	O
in	O
detail	O
the	O
latest	O
tactics	O
,	O
techniques	O
,	O
and	O
procedures	O
(	O
TTPs	O
)	O
observed	O
in	O
cyberattacks	O
from	O
the	O
Cozy	O
Bear	O
state	O
-	O
sponsored	O
hackers	O
.	O
While	O
some	O
of	O
the	O
techniques	O
are	O
somewhat	O
common	O
today	O
,	O
Cozy	O
Bear	O
has	O
been	O
using	O
them	O
long	O
before	O
they	O
became	O
popular	O
:	O
credential	O
hopping	O
hijacking	O
Office	O
365	O
(	O
O365	O
)	O
Service	O
Principal	O
and	O
Application	O
bypassing	O
multi	O
-	O
factor	O
authentication	O
(	O
MFA	O
)	O
by	O
stealing	O
browser	O
cookies	O
stealing	O
credentials	O
using	O
Get	O
-	O
ADReplAccount	O
Credential	O
hopping	O
was	O
the	O
first	O
stage	O
of	O
the	O
attack	O
,	O
allowing	O
the	O
threat	O
actor	O
to	O
log	O
into	O
Office	O
365	O
from	O
an	O
internal	O
server	O
that	O
the	O
hackers	O
reached	O
through	O
a	O
compromised	O
public	O
-	O
facing	O
system	O
.	O
source	O
:	O
CrowdStrike	O
CrowdStrike	O
says	O
that	O
this	O
technique	O
is	O
hard	O
to	O
spot	O
in	O
environments	O
with	O
little	O
visibility	O
into	O
identity	O
usage	O
since	O
hackers	O
could	O
use	O
more	O
than	O
one	O
domain	O
administrator	O
account	O
.	O
Bypassing	O
MFA	O
to	O
access	O
cloud	O
resources	O
by	O
stealing	O
browser	O
cookies	O
has	O
been	O
used	O
since	O
before	O
2020	O
.	O
CrowdStrike	O
says	O
that	O
APT29	O
kept	O
a	O
low	O
profile	O
after	O
decrypting	O
the	O
authentication	O
cookies	O
,	O
likely	O
offline	O
,	O
by	O
using	O
the	O
Cookie	O
Editor	O
extension	O
for	O
Chrome	O
to	O
replay	O
them	O
;	O
they	O
deleted	O
the	O
extension	O
afterward	O
.	O
“	O
This	O
extension	O
permitted	O
bypassing	O
MFA	O
requirements	O
,	O
as	O
the	O
cookies	O
,	O
replayed	O
through	O
the	O
Cookie	O
Editor	O
extension	O
,	O
allowed	O
the	O
threat	O
actor	O
to	O
hijack	O
the	O
already	O
MFA	O
-	O
approved	O
session	O
of	O
a	O
targeted	O
user	O
”	O
-	O
CrowdStrike	O
This	O
allowed	O
them	O
to	O
move	O
laterally	O
on	O
the	O
network	O
and	O
reach	O
the	O
next	O
stage	O
of	O
the	O
attack	O
,	O
connecting	O
to	O
the	O
victim	O
’s	O
O365	O
tenant	O
for	O
the	O
next	O
stage	O
of	O
the	O
attack	O
.	O
CrowdStrike	O
’s	O
report	O
describes	O
the	O
steps	O
that	O
APT29	O
took	O
to	O
achieve	O
persistence	O
in	O
a	O
position	O
that	O
allowed	O
them	O
to	O
read	O
any	O
email	O
and	O
SharePoint	O
or	O
OneDrive	O
files	O
of	O
the	O
compromised	O
organization	O
.	O
GoldMax	O
for	O
Linux	O
and	O
TrailBlazer	O
During	O
their	O
incident	O
response	O
work	O
on	O
APT29	O
StellarParticle	O
attacks	O
,	O
CrowdStrike	O
’s	O
researchers	O
used	O
the	O
User	O
Access	O
Logging	O
(	O
UAL	O
)	O
database	O
to	O
identify	O
earlier	O
malicious	O
account	O
usage	O
,	O
which	O
led	O
to	O
finding	O
the	O
GoldMax	O
for	O
Linux	O
and	O
TrailBlazer	O
malware	O
.	O
CrowdStrike	O
says	O
that	O
TrailBlazer	O
is	O
a	O
completely	O
new	O
malware	O
family	O
,	O
while	O
GoldMax	O
for	O
Linux	O
backdoor	O
“	O
is	O
almost	O
identical	O
in	O
functionality	O
and	O
implementation	O
to	O
the	O
previously	O
identified	O
May	O
2020	O
Windows	O
variant	O
.	O
”	O
The	O
researchers	O
believe	O
that	O
the	O
little	O
differences	O
are	O
between	O
the	O
two	O
GoldMax	O
versions	O
are	O
due	O
to	O
the	O
continuous	O
improvements	O
from	O
the	O
developer	O
for	O
long	O
-	O
term	O
detection	O
evasion	O
.	O
GoldMax	O
was	O
likely	O
used	O
for	O
persistence	O
(	O
a	O
crontab	O
with	O
a	O
“	O
@reboot	O
”	O
line	O
for	O
a	O
non	O
-	O
root	O
user	O
)	O
over	O
long	O
periods	O
in	O
StellarParticle	O
campaigns	O
.	O
The	O
backdoor	O
stayed	O
undetected	O
by	O
posing	O
as	O
a	O
legitimate	O
file	O
in	O
a	O
hidden	O
directory	O
.	O
The	O
TrailBlazer	O
implant	O
also	O
hid	O
under	O
the	O
name	O
of	O
a	O
legitimate	O
file	O
and	O
it	O
was	O
configured	O
for	O
persistence	O
using	O
the	O
Windows	O
Management	O
Instrumentation	O
(	O
WMI	O
)	O
Event	O
Subscriptions	O
,	O
a	O
relatively	O
new	O
technique	O
in	O
2019	O
,	O
the	O
earliest	O
known	O
date	O
for	O
its	O
deployment	O
on	O
victim	O
systems	O
.	O
TrailBlazer	O
managed	O
to	O
keep	O
communication	O
with	O
the	O
command	O
and	O
control	O
(	O
C2	O
)	O
server	O
covert	O
by	O
masking	O
it	O
as	O
legitimate	O
Google	O
Notifications	O
HTTP	O
requests	O
.	O
CrowdStrike	O
notes	O
that	O
the	O
implant	O
has	O
modular	O
functionality	O
and	O
“	O
a	O
very	O
low	O
prevalence	O
”	O
and	O
that	O
it	O
shares	O
similarities	O
with	O
other	O
malware	O
families	O
used	O
by	O
the	O
same	O
threat	O
actor	O
,	O
such	O
as	O
GoldMax	O
and	O
Sunburst	O
(	O
both	O
used	O
in	O
the	O
SolarWinds	O
supply	O
-	O
chain	O
attack	O
)	O
.	O
Tim	O
Parisi	O
,	O
Director	O
of	O
Professional	O
Services	O
at	O
CrowdStrike	O
,	O
told	O
BleepingComputer	O
that	O
the	O
covert	O
activity	O
of	O
the	O
two	O
malware	O
pieces	O
delayed	O
the	O
discovery	O
of	O
the	O
two	O
malware	O
pieces	O
,	O
as	O
the	O
researchers	O
found	O
them	O
in	O
mid-2021	O
.	O
Recon	O
and	O
move	O
to	O
Office	O
365	O
After	O
gaining	O
access	O
to	O
a	O
target	O
organization	O
’s	O
infrastructure	O
and	O
established	O
persistence	O
,	O
APT29	O
hackers	O
took	O
every	O
opportunity	O
to	O
collect	O
intelligence	O
that	O
would	O
allow	O
them	O
to	O
further	O
the	O
attack	O
.	O
One	O
constant	O
tactic	O
was	O
to	O
draw	O
information	O
from	O
the	O
victim	O
’s	O
internal	O
knowledge	O
repositories	O
,	O
the	O
so	O
-	O
called	O
wikis	O
.	O
These	O
documents	O
can	O
hold	O
sensitive	O
details	O
specific	O
to	O
various	O
services	O
and	O
products	O
in	O
the	O
organization	O
.	O
“	O
This	O
information	O
included	O
items	O
such	O
as	O
product	O
/	O
service	O
architecture	O
and	O
design	O
documents	O
,	O
vulnerabilities	O
and	O
step	O
-	O
by	O
-	O
step	O
instructions	O
to	O
perform	O
various	O
tasks	O
.	O
Additionally	O
,	O
the	O
threat	O
actor	O
viewed	O
pages	O
related	O
to	O
internal	O
business	O
operations	O
such	O
as	O
development	O
schedules	O
and	O
points	O
of	O
contact	O
.	O
In	O
some	O
instances	O
these	O
points	O
of	O
contact	O
were	O
subsequently	O
targeted	O
for	O
further	O
data	O
collection	O
”	O
-	O
CrowdStrike	O
Parisi	O
told	O
us	O
that	O
accessing	O
company	O
wikis	O
was	O
a	O
common	O
APT29	O
reconnaissance	O
activity	O
in	O
the	O
investigated	O
StellarParticle	O
attacks	O
.	O
CrowdStrike	O
’s	O
deep	O
dive	O
into	O
APT29	O
’s	O
StellarParticle	O
campaigns	O
offers	O
details	O
on	O
how	O
the	O
threat	O
actor	O
connected	O
to	O
the	O
victim	O
’s	O
O365	O
tenant	O
through	O
the	O
Windows	O
Azure	O
Active	O
Directory	O
PowerShell	O
Module	O
,	O
and	O
performed	O
enumeration	O
queries	O
for	O
roles	O
,	O
members	O
,	O
users	O
,	O
domains	O
,	O
accounts	O
,	O
or	O
a	O
service	O
principal	O
's	O
credentials	O
.	O
When	O
analyzing	O
the	O
log	O
entries	O
,	O
the	O
researchers	O
noticed	O
that	O
the	O
threat	O
actor	O
also	O
executed	O
the	O
AddServicePrincipalCredentials	O
command	O
.	O
“	O
CrowdStrike	O
analyzed	O
the	O
configuration	O
settings	O
in	O
the	O
victim	O
’s	O
O365	O
tenant	O
and	O
discovered	O
that	O
a	O
new	O
secret	O
had	O
been	O
added	O
to	O
a	O
built	O
-	O
in	O
Microsoft	O
Azure	O
AD	O
Enterprise	O
Application	O
,	O
Microsoft	O
StaffHub	O
Service	O
Principal	O
,	O
which	O
had	O
Application	O
level	O
permissions	O
”	O
-	O
CrowdSrike	O
The	O
adversary	O
had	O
added	O
a	O
new	O
secret	O
to	O
the	O
application	O
and	O
set	O
its	O
validity	O
for	O
more	O
than	O
10	O
years	O
,	O
the	O
researchers	O
note	O
.	O
The	O
permission	O
level	O
obtained	O
this	O
way	O
let	O
hackers	O
access	O
all	O
mail	O
and	O
SharePoint	O
/	O
OneDrive	O
files	O
in	O
the	O
company	O
and	O
allowed	O
them	O
to	O
“	O
create	O
new	O
accounts	O
and	O
assign	O
administrator	O
privileges	O
to	O
any	O
account	O
in	O
the	O
organization	O
.	O
”	O
Maintaining	O
persistence	O
Once	O
Cozy	O
Bear	O
/	O
APT29	O
established	O
persistence	O
in	O
a	O
target	O
organization	O
they	O
would	O
maintain	O
it	O
for	O
as	O
long	O
as	O
possible	O
,	O
sometimes	O
helped	O
by	O
the	O
poor	O
security	O
hygiene	O
of	O
the	O
compromised	O
organization	O
.	O
The	O
longest	O
time	O
the	O
threat	O
actor	O
spent	O
inside	O
an	O
organization	O
was	O
two	O
years	O
,	O
Parisi	O
told	O
BleepingComputer	O
.	O
Persisting	O
this	O
long	O
would	O
not	O
be	O
possible	O
without	O
some	O
effort	O
from	O
the	O
hackers	O
,	O
since	O
organizations	O
often	O
rotate	O
credentials	O
as	O
a	O
security	O
precaution	O
.	O
To	O
prevent	O
losing	O
access	O
,	O
Cozy	O
Bear	O
hackers	O
would	O
periodically	O
refresh	O
the	O
stolen	O
credentials	O
by	O
stealing	O
new	O
ones	O
,	O
oftentimes	O
via	O
Mimikatz	O
.	O
In	O
at	O
least	O
one	O
case	O
,	O
though	O
,	O
the	O
administrators	O
of	O
the	O
compromised	O
company	O
reset	O
their	O
passwords	O
to	O
the	O
same	O
ones	O
,	O
thus	O
defeating	O
the	O
purpose	O
of	O
credential	O
rotation	O
.	O
Cozy	O
Bear	O
hackers	O
are	O
some	O
of	O
the	O
most	O
sophisticated	O
threat	O
actors	O
in	O
the	O
cyber	O
espionage	O
world	O
,	O
with	O
top	O
skills	O
to	O
infiltrate	O
and	O
stay	O
undetected	O
on	O
a	O
company	O
's	O
infrastructure	O
for	O
long	O
periods	O
.	O
During	O
the	O
StellarParticle	O
attacks	O
,	O
they	O
demonstrated	O
expert	O
knowledge	O
in	O
Azure	O
,	O
Office	O
365	O
,	O
and	O
Active	O
Directory	O
management	O
.	O