Rooting or jailbreaking removes the operating system's own boundaries between applications. Once those are gone, no application can protect its data, and that includes any messenger.
What root access lets an attacker do
- Read another app's memory while it runs, which exposes decrypted messages regardless of how well they were encrypted in storage or in transit.
- Reach internal storage that the system normally keeps private to each app.
- Bypass the security features built into the platform, because those features are enforced by the very layer that was disabled.
- Intercept input, including a passcode typed into the app.
Why encryption does not save you here
Encryption protects a message while it travels and while it sits in storage. It cannot protect a message while it is being read, because at that moment it exists in plain form on the screen and in memory. An attacker with root access is inside the device, past the point where encryption applies at all. This is why the honest answer is that the app cannot compensate: the guarantee is not weakened, it is bypassed.
If you use such a device anyway
- Install only from sources you have a specific reason to trust, and read what each app is granted.
- Keep the account protected with two-step verification, so a compromised device does not immediately mean a compromised account everywhere.
- Review Settings, Devices regularly and terminate anything unfamiliar.
- Keep anything genuinely sensitive on a device that has not been modified.
The same reasoning applies to a device with malware, an unofficial modified client, or a work profile administered by someone else. The question is never how strong the encryption is, but who else is inside the device.
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