ThreeHopsAhead

##Some general background

Discord is a privacy and security disaster. They do not make their money through ads and tracking (as of now) but they do not care about privacy or security just the slightest bit either. Discord messages are not end to end encrypted. Discord, their employees and their infrastructure partners like Google Cloud Messaging have access to your messages at all time. Do not ever send anything sensitive over Discord! Discord also does not delete your messages when you delete your account, leave a server or delete a channel or group. When you delete a channel or group or get removed from one your messages still stay on their server. You just lose access to them and have no way to delete them anymore. If you delete your account without deleting your messages first they will stay on their servers forever without you having any way to access or delete them. There is no official way for deleting all your messages. I am not a lawyer, but I am very sure that is a violation of the GDPR and highly illegal. They claim they anonymize that data when you delete your account, but all your messages are still tied to an account ID and there is no way to anonymize private messages that can contain personal information. Using client mods to automate deleting messages is even against their TOS. They do not comply with laws that require them to delete your data and reserve the right to ban you when you try to do that yourself. You should absolutely regularly delete your messages anyways. Make sure to have another mean of contact for your Discord friends so you do not rely on Discord as they can and do of course ban you for any or no reason whatsoever.

Discord also has extremely extensive telemetry that is not anonymized. They basically log every click you make in the app: when you click on a profile, when you join a voice channel etc. You can see this data when you do a GDPR request. Included in this logs is your IP address, your rough location and device information for every single event. You can block some of this with uBo in a browser or with client mods.

##Settings in Discord

• Opt out of personalization and other data sharing.
• Set yourself to invisible/offline. Everyone on every server can see when you are online otherwise and there are bots collecting this information.

##Modifications

• If you can, use Discord in a browser with uBlock Origin.
• Regularly use a script like this to delete your messages.
• Consider using a VPN to hide your IP address and location.
• If you use their mobile app do not grant it storage permission and instead share files from your gallery or file manager with Discord.

##Usage

Assume that absolutely everything you do on Discord – every message you send every word you say in a voice channel, every click you make – gets permanently recorded by Discord and secrete services, gets sold to advertisers either right away or in the future and breached to the public in the future. That is exactly what you risk when using Discord. Use it accordingly and do not share anything sensitive. If you need to discuss something private shift to another platform.

##Some general background

Discord is a privacy and security disaster. They do not make their money through ads and tracking (as of now) but they do not care about privacy or security just the slightest bit either. Discord messages are not end to end encrypted. Discord, their employees and their infrastructure partners like Google Cloud Messaging have access to your messages at all time. Do not ever send anything sensitive over Discord! Discord also does not delete your messages when you delete your account, leave a server or delete a channel or group. When you delete a channel or group or get removed from one your messages still stay on their server. You just lose access to them and have no way to delete them anymore. If you delete your account without deleting your messages first they will stay on their servers forever without you having any way to access or delete them. There is no official way for deleting all your messages. I am not a lawyer, but I am very sure that is a violation of the GDPR and highly illegal. They claim they anonymize that data when you delete your account, but all your messages are still tied to an account ID and there is no way to anonymize private messages that can contain personal information. Using client mods to automate deleting messages is even against their TOS. They do not comply with laws that require them to delete your data and reserve the right to ban you when you try to do that yourself. You should absolutely regularly delete your messages anyways. Make sure to have another mean of contact for your Discord friends so you do not rely on Discord as they can and do of course ban you for any or no reason whatsoever.

Discord also has extremely extensive telemetry that is not anonymized. They basically log every click you make in the app: when you click on a profile, when you join a voice channel etc. You can see this data when you do a GDPR request. Included in this logs is your IP address, your rough location and device information for every single event. You can block some of this with uBo in a browser or with client mods.

##Settings in Discord

• Opt out of personalization and other data sharing.
• Set yourself to invisible/offline. Everyone on every server can see when you are online otherwise and there are bots collecting this information.

##Modifications

• If you can, use Discord in a browser with uBlock Origin.
• Regularly use a script like this to delete your messages.
• Consider using a VPN to hide your IP address and location.
• If you use their mobile app do not grant it storage permission and instead share files from your gallery or file manager with Discord.

##Usage

Assume that absolutely everything you do on Discord – every message you send every word you say in a voice channel, every click you make – gets permanently recorded by Discord and secrete services, gets sold to advertisers either right away or in the future and breached to the public in the future. That is exactly what you risk when using Discord. Use it accordingly and do not share anything sensitive. If you need to discuss something private shift to another platform.

The last two paragraphs can be seen as a brief Tl;Dr.

As you have probably already read a critical vulnerability in Android has been found by a researcher accidentally that allows to bypass the Android lock screen and to unlock the phone without the password on Pixel devices and potentially also many other devices. Here is his original post: https://bugs.xdavidhu.me/google/2022/11/10/accidental-70k-google-pixel-lock-screen-bypass/

Tl;Dr: When the phone is locked an attacker can swap the SIM card to their own while on the password entry screen. The device will then show the unlock SIM screen on top of the lockscreen password entry screen. Now the attacker can intentionally enter an incorrect PIN to their SIM card three times causing the SIM card to get locked and requiring the PUK code. When the attacker enters their PUK to unlock the SIM card again and then sets any new SIM pin the phone will unlock without requiring the lockscreen password. All the attacker needs is access to the locked phone, that just needs to have been unlocked once since the last boot and any SIM card they know the PUK of.

The vulnerability is in AOSP and could therefore also affect other non Pixel devices depending on whether the OS uses the AOSP or a customized variant of the lock screen and PIN screen. The vulnerability has been fixed in the November Android security update. So if you are on a Pixel make sure to update your phone quickly and check that you have the November security patch. I read somewhere that the vulnerability got introduced with Android 12, but I cannot verify this. All Android devices without the November 2022 security patch are potentially vulnerable until confirmed otherwise. Even if they are not vulnerable the unlock system before that security patch had significant security issues that made this vulnerability possible and could lead to other similar vulnerabilities being found.

I can personally confirm that the exploit is working on GraphneOS prior to the November security patch.

What to do now

The most important thing is of course to update the OS to get the patch. But there is one huge catch: many manufacturers take very long to incorporate the Android security updates into their custom Android variants and to publish security updates. Even worse many Android devices are no longer supported by the manufacturer and do not get security updates anymore at all. This means many potentially vulnerable Android devices are unpatched and there is no patch available. If your device is still supported you should pay especial close attention to updates in the next time and install them timely. Devices no longer officially supported might have custom ROMs with newer AOSP security updates available (e.g. GrapheneOS has the November security patch for the Pixel 4 and Pixel 4 XL). However custom ROMs can come with their own issues and are not a solution for the huge number of average users.

Mitigations and general advice

Since some time Android encrypts user data with filesystem encryption. When you boot your phone the data is encrypted and not accessible until your enter the password so it can get decrypted. A lockscreen bypass cannot bypass encryption. There is a huge difference whether your device is freshly booted and all user data is at rest and encrypted or whether it is just locked. Once you enter the password Android stores the encryption keys in memory and loads data to memory. Now your user data is accessible to Android and only the lockscreen protects it against someone with physical access. A lockscreen is generally much less secure than encryption. There is significantly more attack surface once you unlock your device after boot as this vulnerability shows. Also biometric authentication is only available after the first unlock which is more vulnerable to different attacks like forced unlocking or tampering and faked biometrics.

What this means is that when you shutdown your device or reboot it, it is invulnerable to this lockscreen bypass as it is protected by something much stronger: encryption. Only once you enter the password again it becomes vulnerable.

The following is good advice in general but especially important now for people with unpatched devices:

(Tl;Dr:)

If you get into a situation where your device is more susceptible to physical access by others such as border control, a police control, anything like that or you let your device unsupervised somewhere or store it somewhere without using it for some time, turn off or reboot your device beforehand. This will make sure all user data is encrypted at rest and significantly reduces attack surface for a physical attacker.

Of course every encryption and every lock screen is just as secure as the password. This is also a good example of why security update support is important. When buying a device, pay attention to the time frame for guaranteed security updates. Also be careful about how long different Android manufacturers take to publish security updates. Generally Android variants closer to AOSP like Pixel stock Android or Graphene OS get security updates quickly while heavily modified manufacturer variants like Samsung's One UI, Huawei's EMUI or Xiaomi's MIUI take much longer.

The last two paragraphs can be seen as a brief Tl;Dr.

As you have probably already read a critical vulnerability in Android has been found by a researcher accidentally that allows to bypass the Android lock screen and to unlock the phone without the password on Pixel devices and potentially also many other devices. Here is his original post: https://bugs.xdavidhu.me/google/2022/11/10/accidental-70k-google-pixel-lock-screen-bypass/

Tl;Dr: When the phone is locked an attacker can swap the SIM card to their own while on the password entry screen. The device will then show the unlock SIM screen on top of the lockscreen password entry screen. Now the attacker can intentionally enter an incorrect PIN to their SIM card three times causing the SIM card to get locked and requiring the PUK code. When the attacker enters their PUK to unlock the SIM card again and then sets any new SIM pin the phone will unlock without requiring the lockscreen password. All the attacker needs is access to the locked phone, that just needs to have been unlocked once since the last boot and any SIM card they know the PUK of.

The vulnerability is in AOSP and could therefore also affect other non Pixel devices depending on whether the OS uses the AOSP or a customized variant of the lock screen and PIN screen. The vulnerability has been fixed in the November Android security update. So if you are on a Pixel make sure to update your phone quickly and check that you have the November security patch. I read somewhere that the vulnerability got introduced with Android 12, but I cannot verify this. All Android devices without the November 2022 security patch are potentially vulnerable until confirmed otherwise. Even if they are not vulnerable the unlock system before that security patch had significant security issues that made this vulnerability possible and could lead to other similar vulnerabilities being found.

I can personally confirm that the exploit is working on GraphneOS prior to the November security patch.

What to do know

The most important thing is of course to update the OS to get the patch. But there is one huge catch: many manufacturers take very long to incorporate the Android security updates into their custom Android variants and to publish security updates. Even worse many Android devices are no longer supported by the manufacturer and do not get security updates anymore at all. This means many potentially vulnerable Android devices are unpatched and there is no patch available. If your device is still supported you should pay especial close attention to updates in the next time and install them timely. Devices no longer officially supported might have custom ROMs with newer AOSP security updates available (e.g. GrapheneOS has the November security patch for the Pixel 4 and Pixel 4 XL). However custom ROMs can come with their own issues and are not a solution for the huge number of average users.

Mitigations and general advice

Since some time Android encrypts user data with filesystem encryption. When you boot your phone the data is encrypted and not accessible until your enter the password so it can get decrypted. A lockscreen bypass cannot bypass encryption. There is a huge difference whether your device is freshly booted and all user data is at rest and encrypted or whether it is just locked. Once you enter the password Android stores the encryption keys in memory and loads data to memory. Now your user data is accessible to Android and only the lockscreen protects it against someone with physical access. A lockscreen is generally much less secure than encryption. There is significantly more attack surface once you unlock your device after boot as this vulnerability shows. Also biometric authentication is only available after the first unlock which is more vulnerable to different attacks like forced unlocking or tampering and faked biometrics.

What this means is that when you shutdown your device or reboot it, it is invulnerable to this lockscreen bypass as it is protected by something much stronger: encryption. Only once you enter the password again it becomes vulnerable.

The following is good advice in general but especially important now for people with unpatched devices:

(Tl;Dr:)

If you get into a situation where your device is more susceptible to physical access by others such as border control, a police control, anything like that or you let your device unsupervised somewhere or store it somewhere without using it for some time, turn off or reboot your device beforehand. This will make sure all user data is encrypted at rest and significantly reduces attack surface for a physical attacker.

Of course every encryption and every lock screen is just as secure as the password. This is also a good example of why security update support is important. When buying a device, pay attention to the time frame for guaranteed security updates. Also be careful about how long different Android manufacturers take to publish security updates. Generally Android variants closer to AOSP like Pixel stock Android or Graphene OS get security updates quickly while heavily modified manufacturer variants like Samsung's One UI, Huawei's EMUI or Xiaomi's MIUI take much longer.

The last two paragraphs can be seen as a brief Tl;Dr.

As you have probably already read a critical vulnerability in Android has been found by a researcher accidentally that allows to bypass the Android lock screen and to unlock the phone without the password on Pixel devices and potentially also many other devices. Here is his original post: https://bugs.xdavidhu.me/google/2022/11/10/accidental-70k-google-pixel-lock-screen-bypass/

Tl;Dr: When the phone is locked an attacker can swap the SIM card to their own while on the password entry screen. The device will then show the unlock SIM screen on top of the lockscreen password entry screen. Now the attacker can intentionally enter an incorrect PIN to their SIM card three times causing the SIM card to get locked and requiring the PUK code. When the attacker enters their PUK to unlock the SIM card again and then sets any new SIM pin the phone will unlock without requiring the lockscreen password. All the attacker needs is access to the locked phone, that just needs to have been unlocked once since the last boot and any SIM card they know the PUK of.

The vulnerability is in AOSP and could therefore also affect other non Pixel devices depending on whether the OS uses the AOSP or a customized variant of the lock screen and PIN screen. The vulnerability has been fixed in the November Android security update. So if you are on a Pixel make sure to update your phone quickly and check that you have the November security patch. I read somewhere that the vulnerability got introduced with Android 12, but I cannot verify this. All Android devices without the November 2022 security patch are potentially vulnerable until confirmed otherwise. Even if they are not vulnerable the unlock system before that security patch had significant security issues that made this vulnerability possible and could lead to other similar vulnerabilities being found.

I can personally confirm that the exploit is working on GraphneOS prior to the November security patch.

What to do know

The most important thing is of course to update the OS to get the patch. But there is one huge catch: many manufacturers take very long to incorporate the Android security updates into their custom Android variants and to publish security updates. Even worse many Android devices are no longer supported by the manufacturer and do not get security updates anymore at all. This means many potentially vulnerable Android devices are unpatched and there is no patch available. If your device is still supported you should pay especial close attention to updates in the next time and install them timely. Devices no longer officially supported might have custom ROMs with newer AOSP security updates available (e.g. GrapheneOS has the November security patch for the Pixel 4 and Pixel 4 XL). However custom ROMs can come with their own issues and are not a solution for the huge number of average users.

Mitigations and general advice

Since some time Android encrypts user data with filesystem encryption. When you boot your phone the data is encrypted and not accessible until your enter the password so it can get decrypted. A lockscreen bypass cannot bypass encryption. There is a huge difference whether your device is freshly booted and all user data is at rest and encrypted or whether it is just locked. Once you enter the password Android stores the encryption keys in memory and loads data to memory. Now your user data is accessible to Android and only the lockscreen protects it against someone with physical access. A lockscreen is generally much less secure than encryption. There is significantly more attack surface once you unlock your device after boot as this vulnerability shows. Also biometric authentication is only available after the first unlock which is more vulnerable to different attacks like forced unlocking or tampering and faked biometrics.

What this means is that when you shutdown your device or reboot it, it is invulnerable to this lockscreen bypass as it is protected by something much stronger: encryption. Only once you enter the password again it becomes vulnerable.

The following is good advice in general but especially important now for people with unpatched devices:

(Tl;Dr:)

If you get into a situation where your device is more susceptible to physical access by others such as border control, a police control, anything like that or you let your device unsupervised somewhere or store it somewhere without using it for some time, turn off or reboot your device beforehand. This will make sure all user data is encrypted at rest and significantly reduces attack surface for a physical attacker.

Of course every encryption and every lock screen is just as secure as the password. This is also a good example of why security update support is important. When buying a device, pay attention to the time frame for guaranteed security updates. Also be careful about how long different Android manufacturers take to publish security updates. Generally Android variants closer to AOSP like Pixel stock Android or Graphene OS get security updates quickly while heavily modified manufacturer variants like Samsung's One UI, Huawei's EMUI or Xiaomi's MIUI take much longer.

The surveillance state in one sentence

You are guilty until you prove otherwise by every part of your private life being surveiled. If you have any issue with this that is just proof of your guilt. What would you have to hide otherwise?