Welcome back, digital investigators!

Many of our messengers sit somewhere between privacy and routine. People treat chats like a private conversation and because it feels comfortable, they often share things they wouldn’t say on social media. The data stored in those apps is valuable for forensics. It may have chats, media and group membership with timestamps. Using this data we can reconstruct events. 

We’re going to take a close look at WhatsApp forensics today and show you the artifacts you can find on Android and iOS. It’ll be a deep dive on how WhatsApp keeps its data and what those files contain. All of it in plain language.

At Hackers-Arise we assist people with forensic investigations to uncover cybercrime and help with incident response. WhatsApp is part of that.

WhatsApp Artifacts on Android Devices

On Android, WhatsApp stores its private app data inside the device’s user data area. You will find the app’s files under /data/data/com.whatsapp/ or equivalently /data/user/0/com.whatsapp/ on many devices. These directories are not accessible without root, so to read them directly you need a physical dump of the file system or root. If you do not have root or a physical image, your options are restricted to logical backups.

There are two important files here: wa.db and msgstore.db. Both are SQLite databases and together they form the core of WhatsApp evidence.

wa.db is the contacts database. It has the WhatsApp user’s contacts with phone numbers, display names, status, timestamps for when contacts were created or changed. You can open the file with a SQLite browser to see its tables. The interesting tables here are those that store contact records (wa_contacts or similar), sqlite_sequence that has auto-increment counts and android_metadata with app language.

Wa.db is basically the address book for WhatsApp. It has names, numbers and a little context for each contact.

msgstore.db is the message store. This database has sent and received messages, timestamps, message status, senders and receivers and references to media files. In many WhatsApp versions you will find tables that include a general information table (sqlite_sequence), a full text index table for message content (message_fts_content or similar), the main messages table which usually contains the message body and metadata, messages_thumbnails which has images and their timestamps, and a chat_list table that stores chat entries. 

Be aware that WhatsApp changes its structure and field names may change between versions. Newer schema versions may include extra fields such as media_enc_hash, edit_version, or payment_transaction_id. So you need to inspect the schema first.

On many Android devices WhatsApp also keeps encrypted backups in a public storage location that you can find under /data/media/0/WhatsApp/Databases/ (the virtual SD card)

or /mnt/sdcard/WhatsApp/Databases/ for physical SD cards. Those backup files look like msgstore.db.cryptXX, where XX shows the cryptographic scheme version. 

The msgstore.db.cryptXX files are an encrypted copy of msgstore.db intended for device backups. To decrypt them you need a cryptographic key that WhatsApp stores privately on the device. The key can usually be found here: /data/data/com.whatsapp/files/. Without that key those encrypted backups are not readable.

Other important Android files and directories to examine include the preferences and registration XMLs in /data/data/com.whatsapp/shared_prefs/. The file com.whatsapp_preferences.xml often contains profile details and configuration. A fragment of such a file may show the phone number associated with the account, the app version, a profile message such as “Hey there! I am using WhatsApp” and the account display name. The registration.RegisterPhone.xml file typically has registration metadata like the phone number and regional format. 

The axolotl.db file in /data/data/com.whatsapp/databases/ holds cryptographic keys (used in the Signal/Double Ratchet protocol implementation) and account identification data. chatsettings.db has app settings. Logs are kept under /data/data/com.whatsapp/files/Logs/ and may include whatsapp.log as well as compressed rotated backups looking like whatsapp-YYYY-MM-DD.1.log.gz. They show app activity and errors.

Media is often stored in the media tree on internal or external storage:

/data/media/0/WhatsApp/Media/WhatsApp Images/ for images,

/data/media/0/WhatsApp/Media/WhatsApp Voice Notes/ for voice messages (usually Opus format), WhatsApp Audio, WhatsApp Video, and WhatsApp Profile Photos.

Within the app’s private area you may also find cached profile pictures under /data/data/com.whatsapp/cache/Profile Pictures/ and avatar thumbnails under /data/data/com.whatsapp/files/Avatars/. Some avatar thumbnails use a .j extension, but those are just JPEG files.

If the device uses an SD card, a WhatsApp directory at the card’s root may store copies of shared files (/mnt/sdcard/WhatsApp/.Share/), a trash folder for deleted content (/mnt/sdcard/WhatsApp/.trash/), and the Databases subdirectory with encrypted backups and media subfolders mirroring those on internal storage. Deleted files in .trash folders can be used to recover media.

Keep in mind, some vendors may add features that change where app data is stored. For example, certain Xiaomi phones implement a “Second Space” feature that creates a second user workspace. WhatsApp in the second workspace stores its data under a different user ID path. That means it may be under /data/user/10/com.whatsapp/databases/wa.db rather than the usual /data/user/0/com.whatsapp/databases/wa.db

WhatsApp Artifacts on iOS Devices

On iOS, WhatsApp centralizes its data into a few places and all that data is commonly accessible via device backups. The main application database is often ChatStorage.sqlite located under /private/var/mobile/Applications/group.net.whatsapp.WhatsApp.shared/ but some forensic tools may display this as AppDomainGroup-group.net.whatsapp.WhatsApp.shared

Within ChatStorage.sqlite the interesting tables are ZWAMESSAGE and ZWAMEDIAITEM. The first one stores message records and the other one has metadata for attachments and media items. ZWAPROFILEPUSHNAME and ZWAPROFILEPICTUREITEM map WhatsApp identifiers to display names and avatars. The table Z_PRIMARYKEY may have general database metadata such as record counts.

iOS also places supporting files in the group container. BackedUpKeyValue.sqlite can contain cryptographic keys and data for identifying account ownership. ContactsV2.sqlite stores contact details which include names, phone numbers, profile statuses and WhatsApp IDs. The consumer_version file holds the app version and current_wallpaper.jpg (or wallpaper in older versions) has the background image used in WhatsApp chats. The blockedcontacts.dat file lists blocked numbers, and pw.dat can hold an encrypted password. net.whatsapp.WhatsApp.plist or group.net.whatsapp.WhatsApp.shared.plist store profile settings.

Thumbnails, avatars and media are stored under /private/var/mobile/Applications/group.net.whatsapp.WhatsApp.shared/Media/Profile/ and /private/var/mobile/Applications/group.net.whatsapp.WhatsApp.shared/Message/Media/. WhatsApp logs (calls.log and calls.backup.log) can be found in the Documents or Library/Logs folders and will have information on call activity.

iOS devices are often backed up through iTunes or Finder, so you can extract WhatsApp artifacts from a device backup without a full file system image. If the backup is unencrypted it may include the ChatStorage.sqlite file and associated media. If the backup is encrypted you will need the backup password or legal access methods to decrypt it. Many investigators create a forensic backup and then examine the WhatsApp databases with a SQLite viewer and other forensic tools (Belkasoft) that understands this WhatsApp schema differences across versions.

Summary

Plainly speaking, WhatsApp forensics can help us understand who a suspect interacted with by viewing chat histories with timestamps, media files, message status (sent, delivered, read), groups, profile names and avatars and more. We understand this data can be accessed without authorization, violating people’s privacy, so part of our goal here was to show just how much data is actually stored on your phone. If you’re part of a sensitive group, look for other secure alternatives to WhatsApp and make sure your chats get deleted regularly to prevent unauthorized access to them. Disable cloud backups and try not to store those backups locally either. Even encrypted ones be cracked open by brute forcing the password.

If you’re interested in mobile forensics, you can join our training. We will walk you through the essentials of Android and iOS, explaining how evidence is stored on these devices. You will learn how investigators extract and analyze data, work with labs that involve finding hidden apps, working with encrypted chats and more.

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