Malicious
32
/62

Threat

com.rayark.Cytus.full

邀请函

Analyzed on 2022-10-02T23:17:52.179130

14

permissions

3

activities

3

services

7

receivers

0

domains

File sums

MD5 0381e9cd75d8fe208d2ebc85eea0112e
SHA1 e5244f356b86c41610639d507bea024f22351940
SHA256 637960c2a1824272b9de2e4ddd7b1f3255921e21693fac9d5a22a69a731c0666
Size 0.42MB

APKiD

Information computed with APKiD.

/tmp/tmpj81qpwqa!classes.dex
compiler
  • dexlib 2.x

SSdeep

Information computed with ssdeep.

APK file 6144:/OgW/4AfwT7/zVoXfc0os0ROLqQkDih776I+q3yPQk6FWN3VJA9dvshor9GjoCd2:/OgfA5vGs0R2qxo6ITxlIhSwjoIdfULD
Manifest 192:EqdgS79WTbPl++9a1POvywOpgaswGGG4u8IXY/C126+91TStcSkDu6hSHQ6lLE8l:…
classes.dex 12288:My3+ETW39lBY28FxWIfxGiguoxWYQ6gut5xKgXmQBZ68S1rCJ3K+4W5rsvJENVo…

Dexofuzzy

Information computed with Dexofuzzy.

APK file 768:oOWekbZL8+55H0s1+yigb19hI8pM02IBSOanSiEvJeV9rzm1:pkS+55H0TyjG0RBS…
classes.dex 768:oOWekbZL8+55H0s1+yigb19hI8pM02IBSOanSiEvJeV9rzm1:pkS+55H0TyjG0RBS…

APK details

Information computed with AndroGuard and Pithus.

Package com.rayark.Cytus.full
App name 邀请函
Version name 5.0.0
Version code 500
SDK 8 - 21
UAID 584f3ec911e4b9b9e4db4a0e98f2aa1e83247ed8
Signature Signature V1
Frosting Not frosted

Certificate details

Information computed with AndroGuard.

MD5 e89b158e4bcf988ebd09eb83f5378e87
SHA1 61ed377e85d386a8dfee6b864bd85b0bfaa5af81
SHA256 a40da80a59d170caa950cf15c18c454d47a39b26989d8b640ecd745ba71bf5dc
Issuer Email Address: android@android.com, Common Name: Android, Organizational Unit: Android, Organization: Android, Locality: Mountain View, State/Province: California, Country: US
Not before 2008-02-29T01:33:46+00:00
Not after 2035-07-17T01:33:46+00:00

Manifest analysis

Information computed with MobSF.

Medium Application Data can be Backed up[android:allowBackup=true]
This flag allows anyone to backup your application data via adb. It allows users who have enabled USB debugging to copy application data off of the device.
High Broadcast Receiver (ashdun.meaimai.TelInternal) is not Protected.An intent-filter exists.
A Broadcast Receiver is found to be shared with other apps on the device therefore leaving it accessible to any other application on the device. The presence of intent-filter indicates that the Broadcast Receiver is explicitly exported.
High Broadcast Receiver (ashdun.meaimai.BootReceiver) is not Protected.An intent-filter exists.
A Broadcast Receiver is found to be shared with other apps on the device therefore leaving it accessible to any other application on the device. The presence of intent-filter indicates that the Broadcast Receiver is explicitly exported.
High Broadcast Receiver (ashdun.meaimai.NetstateReceiver) is not Protected.An intent-filter exists.
A Broadcast Receiver is found to be shared with other apps on the device therefore leaving it accessible to any other application on the device. The presence of intent-filter indicates that the Broadcast Receiver is explicitly exported.
High Broadcast Receiver (ashdun.meaimai.SmsReceiver) is not Protected.An intent-filter exists.
A Broadcast Receiver is found to be shared with other apps on the device therefore leaving it accessible to any other application on the device. The presence of intent-filter indicates that the Broadcast Receiver is explicitly exported.
High Activity (ashdun.meaimai.UninstallerActivity) is not Protected.An intent-filter exists.
An Activity is found to be shared with other apps on the device therefore leaving it accessible to any other application on the device. The presence of intent-filter indicates that the Activity is explicitly exported.
High Broadcast Receiver (ashdun.meaimai.MyAdmin) is Protected by a permission, but the protection level of the permission should be checked.
Permission: android.permission.BIND_DEVICE_ADMIN [android:exported=true]
A Broadcast Receiver is found to be shared with other apps on the device therefore leaving it accessible to any other application on the device. It is protected by a permission which is not defined in the analysed application. As a result, the protection level of the permission should be checked where it is defined. If it is set to normal or dangerous, a malicious application can request and obtain the permission and interact with the component. If it is set to signature, only applications signed with the same certificate can obtain the permission.
High Broadcast Receiver (ashdun.meaimai.SmsReceiver4_4) is Protected by a permission, but the protection level of the permission should be checked.
Permission: android.permission.BROADCAST_SMS [android:exported=true]
A Broadcast Receiver is found to be shared with other apps on the device therefore leaving it accessible to any other application on the device. It is protected by a permission which is not defined in the analysed application. As a result, the protection level of the permission should be checked where it is defined. If it is set to normal or dangerous, a malicious application can request and obtain the permission and interact with the component. If it is set to signature, only applications signed with the same certificate can obtain the permission.
High Broadcast Receiver (ashdun.meaimai.MmsReceiver4_4) is Protected by a permission, but the protection level of the permission should be checked.
Permission: android.permission.BROADCAST_WAP_PUSH [android:exported=true]
A Broadcast Receiver is found to be shared with other apps on the device therefore leaving it accessible to any other application on the device. It is protected by a permission which is not defined in the analysed application. As a result, the protection level of the permission should be checked where it is defined. If it is set to normal or dangerous, a malicious application can request and obtain the permission and interact with the component. If it is set to signature, only applications signed with the same certificate can obtain the permission.
High Activity (ashdun.meaimai.ComposeSmsActivity) is not Protected.An intent-filter exists.
An Activity is found to be shared with other apps on the device therefore leaving it accessible to any other application on the device. The presence of intent-filter indicates that the Activity is explicitly exported.
High Service (ashdun.meaimai.MainService4_4) is Protected by a permission, but the protection level of the permission should be checked.
Permission: android.permission.SEND_RESPOND_VIA_MESSAGE [android:exported=true]
A Service is found to be shared with other apps on the device therefore leaving it accessible to any other application on the device. It is protected by a permission which is not defined in the analysed application. As a result, the protection level of the permission should be checked where it is defined. If it is set to normal or dangerous, a malicious application can request and obtain the permission and interact with the component. If it is set to signature, only applications signed with the same certificate can obtain the permission.
Medium High Intent Priority (2147483647)[android:priority]
By setting an intent priority higher than another intent, the app effectively overrides other requests.
Medium High Intent Priority (2147483647)[android:priority]
By setting an intent priority higher than another intent, the app effectively overrides other requests.
Medium High Intent Priority (2147483647)[android:priority]
By setting an intent priority higher than another intent, the app effectively overrides other requests.

Browsable activities

Information computed with MobSF.

ashdun.meaimai.ComposeSmsActivity

Schemes: sms:// smsto:// mms:// mmsto://

Main Activity

Information computed with AndroGuard.

ashdun.meaimai.MainActivity

Activities

Information computed with AndroGuard.

ashdun.meaimai.MainActivity
ashdun.meaimai.UninstallerActivity
ashdun.meaimai.ComposeSmsActivity

Receivers

Information computed with AndroGuard.

ashdun.meaimai.TelInternal
ashdun.meaimai.BootReceiver
ashdun.meaimai.NetstateReceiver
ashdun.meaimai.SmsReceiver
ashdun.meaimai.MyAdmin
ashdun.meaimai.SmsReceiver4_4
ashdun.meaimai.MmsReceiver4_4

Services

Information computed with AndroGuard.

ashdun.meaimai.MainService
ashdun.meaimai.PhoService
ashdun.meaimai.MainService4_4

Sample timeline

Certificate valid not before Feb. 29, 2008, 1:33 a.m.
Oldest file found in APK Sept. 4, 2018, 9:09 a.m.
Latest file found in APK Sept. 4, 2018, 9:09 a.m.
First submission on VT Dec. 25, 2018, 3:33 a.m.
Last submission on VT July 24, 2020, 3:54 p.m.
Upload on Pithus Oct. 2, 2022, 11:17 p.m.
Certificate valid not after July 17, 2035, 1:33 a.m.

VirusTotal

Score 32/62
Report https://www.virustotal.com/gui/file/637960c2a1824272b9de2e4ddd7b1f3255921e21693fac9d5a22a69a731c0666/detection

Most Popular AV Detections

Provided by VirusTotal

Threat name: smsthief Identified 7 times
Threat name: smsspy Identified 3 times
Threat name: andr Identified 2 times

NIAP analysis

Information computed with MobSF.

FCS_RBG_EXT.1.1 The application invoke platform-provided DRBG functionality for its cryptographic operations.
Random Bit Generation Services
FCS_STO_EXT.1.1 The application does not store any credentials to non-volatile memory.
Storage of Credentials
FCS_CKM_EXT.1.1 The application generate no asymmetric cryptographic keys.
Cryptographic Key Generation Services
FDP_DEC_EXT.1.1 The application has access to ['network connectivity'].
Access to Platform Resources
FDP_DEC_EXT.1.2 The application has access to ['address book', 'system logs'].
Access to Platform Resources
FDP_NET_EXT.1.1 The application has user/application initiated network communications.
Network Communications
FDP_DAR_EXT.1.1 The application does not encrypt files in non-volatile memory.
Encryption Of Sensitive Application Data
FMT_MEC_EXT.1.1 The application invoke the mechanisms recommended by the platform vendor for storing and setting configuration options.
Supported Configuration Mechanism
FTP_DIT_EXT.1.1 The application does not encrypt any data in traffic or does not transmit any data between itself and another trusted IT product.
Protection of Data in Transit
FCS_RBG_EXT.2.1
FCS_RBG_EXT.2.2
The application perform all deterministic random bit generation (DRBG) services in accordance with NIST Special Publication 800-90A using Hash_DRBG. The deterministic RBG is seeded by an entropy source that accumulates entropy from a platform-based DRBG and a software-based noise source, with a minimum of 256 bits of entropy at least equal to the greatest security strength (according to NIST SP 800-57) of the keys and hashes that it will generate.
Random Bit Generation from Application
FCS_COP.1.1(2) The application perform cryptographic hashing services not in accordance with FCS_COP.1.1(2) and uses the cryptographic algorithm RC2/RC4/MD4/MD5.
Cryptographic Operation - Hashing

Code analysis

Information computed with MobSF.

Low
CVSS:7.5
The App logs information. Sensitive information should never be logged.
MASVS: MSTG-STORAGE-3
CWE-532 Insertion of Sensitive Information into Log File
Files:
 ashdun/meaimai/c.java
com/sun/mail/imap/protocol/BODYSTRUCTURE.java
ashdun/meaimai/i.java
ashdun/meaimai/MyAdmin.java
ashdun/meaimai/j.java
com/sun/mail/dsn/DeliveryStatus.java
ashdun/meaimai/d.java
ashdun/meaimai/l.java
ashdun/meaimai/b/b.java
ashdun/meaimai/TelInternal.java
ashdun/meaimai/BootReceiver.java
ashdun/meaimai/MainActivity.java
ashdun/meaimai/k.java
com/sun/activation/registries/LogSupport.java
ashdun/meaimai/e.java
ashdun/meaimai/deng/c.java
ashdun/meaimai/b/c.java
javax/mail/internet/MailDateFormat.java
ashdun/meaimai/a/f.java
Medium
CVSS:7.4
Files may contain hardcoded sensitive information like usernames, passwords, keys etc.
MASVS: MSTG-STORAGE-14
CWE-312 Cleartext Storage of Sensitive Information
M9: Reverse Engineering
Files:
 com/sun/mail/imap/IMAPStore.java
Medium
CVSS:7.4
MD5 is a weak hash known to have hash collisions.
MASVS: MSTG-CRYPTO-4
CWE-327 Use of a Broken or Risky Cryptographic Algorithm
M5: Insufficient Cryptography
Files:
 com/sun/mail/smtp/DigestMD5.java
com/sun/mail/pop3/Protocol.java

Permissions analysis

Information computed with MobSF.

High android.permission.READ_SMS read SMS or MMS
Allows application to read SMS messages stored on your phone or SIM card. Malicious applications may read your confidential messages.
High android.permission.WRITE_SMS edit SMS or MMS
Allows application to write to SMS messages stored on your phone or SIM card. Malicious applications may delete your messages.
High android.permission.SEND_SMS send SMS messages
Allows application to send SMS messages. Malicious applications may cost you money by sending messages without your confirmation.
High android.permission.RECEIVE_SMS receive SMS
Allows application to receive and process SMS messages. Malicious applications may monitor your messages or delete them without showing them to you.
High android.permission.READ_PHONE_STATE read phone state and identity
Allows the application to access the phone features of the device. An application with this permission can determine the phone number and serial number of this phone, whether a call is active, the number that call is connected to and so on.
High android.permission.READ_CONTACTS read contact data
Allows an application to read all of the contact (address) data stored on your phone. Malicious applications can use this to send your data to other people.
High android.permission.RECEIVE_WAP_PUSH receive WAP
Allows application to receive and process WAP messages. Malicious applications may monitor your messages or delete them without showing them to you.
High android.permission.RECEIVE_MMS receive MMS
Allows application to receive and process MMS messages. Malicious applications may monitor your messages or delete them without showing them to you.
High android.permission.CALL_PHONE directly call phone numbers
Allows the application to call phone numbers without your intervention. Malicious applications may cause unexpected calls on your phone bill. Note that this does not allow the application to call emergency numbers.
High android.permission.PROCESS_OUTGOING_CALLS intercept outgoing calls
Allows application to process outgoing calls and change the number to be dialled. Malicious applications may monitor, redirect or prevent outgoing calls.
High android.permission.READ_LOGS read sensitive log data
Allows an application to read from the system's various log files. This allows it to discover general information about what you are doing with the phone, potentially including personal or private information.
Low android.permission.INTERNET full Internet access
Allows an application to create network sockets.
Low android.permission.ACCESS_NETWORK_STATE view network status
Allows an application to view the status of all networks.
Low android.permission.ACCESS_WIFI_STATE view Wi-Fi status
Allows an application to view the information about the status of Wi-Fi.

Threat analysis

Information computed with Quark-Engine.

Confidence:
100%
Load external class
Confidence:
100%
Method reflection
Confidence:
100%
Load class from given class name
Confidence:
100%
Read sensitive data(SMS, CALLLOG, etc)
Confidence:
100%
Implicit intent(view a web page, make a phone call, etc.) via setData
Confidence:
100%
Monitor the broadcast action events (BOOT_COMPLETED)
Confidence:
100%
Method reflection
Confidence:
100%
Hide the current app's icon
Confidence:
100%
Send SMS
Confidence:
100%
Query data from URI (SMS, CALLLOGS)
Confidence:
100%
Initialize class object dynamically
Confidence:
80%
Create a secure socket connection to the given host address
Confidence:
80%
Query the IMSI number
Confidence:
80%
Get calendar information
Confidence:
80%
Query the phone number
Confidence:
80%
Get specific method from other Dex files

Behavior analysis

Information computed with MobSF.

Certificate handling
       com/sun/mail/util/SocketFetcher.java
Get phone number
       ashdun/meaimai/g.java
Get subscriber id
       ashdun/meaimai/g.java
Get system service
       ashdun/meaimai/MainActivity.java
ashdun/meaimai/g.java
ashdun/meaimai/NetstateReceiver.java
ashdun/meaimai/TelInternal.java
ashdun/meaimai/BootReceiver.java
Inter process communication
       com/a/a/a/b.java
ashdun/meaimai/b/a.java
ashdun/meaimai/MainService.java
ashdun/meaimai/MyAdmin.java
ashdun/meaimai/b/b.java
ashdun/meaimai/TelInternal.java
ashdun/meaimai/BootReceiver.java
ashdun/meaimai/MainActivity.java
ashdun/meaimai/MmsReceiver4_4.java
ashdun/meaimai/deng/c.java
ashdun/meaimai/PhoService.java
ashdun/meaimai/SmsReceiver.java
ashdun/meaimai/NetstateReceiver.java
ashdun/meaimai/b/c.java
ashdun/meaimai/SmsReceiver4_4.java
ashdun/meaimai/h.java
ashdun/meaimai/MainService4_4.java
com/a/a/a/c.java
Java reflection
       myjava/awt/datatransfer/DataFlavor.java
javax/activation/MailcapCommandMap.java
javax/activation/ActivationDataFlavor.java
javax/mail/Session.java
com/sun/mail/pop3/POP3Store.java
com/sun/mail/util/SocketFetcher.java
com/sun/mail/imap/protocol/IMAPProtocol.java
ashdun/meaimai/TelInternal.java
Local file i/o operations
       ashdun/meaimai/MainActivity.java
ashdun/meaimai/c.java
ashdun/meaimai/deng/c.java
ashdun/meaimai/MainService.java
ashdun/meaimai/MainService4_4.java
ashdun/meaimai/UninstallerActivity.java
Message digest
       com/sun/mail/smtp/DigestMD5.java
com/sun/mail/pop3/Protocol.java
Query database of sms, contacts etc
       ashdun/meaimai/c.java
ashdun/meaimai/PhoService.java
ashdun/meaimai/j.java
Send sms
       ashdun/meaimai/b/a.java
Starting activity
       ashdun/meaimai/MainActivity.java
ashdun/meaimai/TelInternal.java
Starting service
       ashdun/meaimai/MainActivity.java
ashdun/meaimai/deng/c.java
ashdun/meaimai/MainService.java
ashdun/meaimai/SmsReceiver.java
ashdun/meaimai/SmsReceiver4_4.java
ashdun/meaimai/MainService4_4.java
ashdun/meaimai/BootReceiver.java
Tcp socket
       com/sun/mail/pop3/Protocol.java
com/sun/mail/smtp/SMTPTransport.java
com/sun/mail/iap/Protocol.java
com/sun/mail/util/SocketFetcher.java
Url connection to file/http/https/ftp/jar
       javax/activation/URLDataSource.java

Control flow graphs analysis

Information computed by Pithus.

The application probably gets the subscriber ID associated to the SIM card/ Should never be collected

The application probably gets the phone number associated to the SIM card

The application probably gets network interfaces addresses (IP and/or MAC)