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Security researchers have raised concerns about how WhatsApp stores chat data on macOS and iOS devices. According to recent findings, message databases may be stored in plaintext inside shared app group containers, potentially exposing sensitive conversations under certain conditions.
Researchers from Mysk reported that WhatsApp uses a shared container linked to Meta applications, identified as group.com.facebook.family. On Apple devices, app group containers allow applications from the same developer to share data and resources.
Because Facebook, Instagram, and WhatsApp belong to the same ecosystem, the shared architecture could introduce privacy and security concerns if exploited alongside operating system vulnerabilities.
Shared Containers Raise Privacy Concerns
The researchers found that WhatsApp chat databases stored inside these containers are not encrypted at rest. This means the data may remain readable if attackers gain access to the device or exploit weaknesses in the operating system.
According to the report, the following risks were identified:
- Chat histories may be stored in plaintext
- Other Meta-owned apps could theoretically access shared data
- Users receive no alerts when such access occurs
- The issue affects both macOS and iOS environments
Researchers also demonstrated that WhatsApp chat histories could be extracted from iPhone backups, where the same unencrypted storage structure was observed.
The findings highlight an important distinction in security design. While WhatsApp uses end-to-end encryption to protect messages during transmission, that protection does not automatically secure data stored locally on the device.
macOS Vulnerability Increases Exposure Risk
The risk becomes more serious when combined with a recently disclosed macOS vulnerability tracked as CVE-2026-28910. The flaw affected Apple’s Archive Utility tool and reportedly allowed attackers to bypass App Sandbox protections.
By abusing this vulnerability, attackers could potentially:
- Access protected application containers
- Extract sensitive information from apps
- Bypass Apple’s Transparency, Consent, and Control protections
- Access chat histories from applications like WhatsApp
Researchers presented a proof-of-concept demonstration showing how the vulnerability could be combined with WhatsApp’s storage behavior to retrieve chat data.
Security Debate Around the Findings
Not all experts agree on the severity of the issue. WABetaInfo stated that although the databases may not be encrypted locally, Apple’s sandboxing system still provides strong isolation between applications.
From this perspective, attackers would still require elevated system privileges or a separate operating system exploit to access the stored data.
However, researchers at Mysk argue that shared app group permissions between Meta applications reduce isolation boundaries and increase the potential attack surface.
The discussion highlights broader concerns about local data protection in modern mobile ecosystems, especially when multiple applications share common storage environments.
Recommendations for Users
Security experts recommend several steps to reduce potential exposure risks:
- Enable encrypted Finder or iTunes backups
- Keep macOS and iOS updated with the latest security patches
- Use strong device passcodes and device encryption
- Limit unnecessary applications from the same developer ecosystem
- Regularly review application permissions and backup settings
At the time of reporting, there were no confirmed cases of widespread exploitation linked to the findings. However, the research highlights the importance of protecting sensitive data not only during transmission but also while stored on devices.
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