CVE-2025-47729 identifies a vulnerability categorized under CWE-912 (Hidden Functionality) in the TeleMessage archiving backend component. TeleMessage markets its TM SGNL app as providing end-to-end encryption from the mobile device through to the corporate archive, ensuring message confidentiality. However, this vulnerability reveals that the backend stores cleartext copies of user messages, a functionality not disclosed in official documentation. This hidden behavior undermines the security guarantees of end-to-end encryption, as sensitive message content is accessible in plaintext on backend systems. The vulnerability was published on May 8, 2025, with a CVSS 3.1 base score of 1.9, reflecting a low severity primarily due to the attack vector being local (AV:L), requiring high privileges (PR:H), and no user interaction (UI:N). The impact is limited to confidentiality loss (C:L), with no integrity or availability effects. No patches or known exploits are currently reported. The vulnerability could be exploited by insiders or attackers who gain privileged access to the archiving backend, allowing them to read sensitive message content that should have been protected by encryption. This discrepancy between advertised security features and actual backend behavior represents a significant trust and compliance issue, especially for organizations handling sensitive or regulated communications.

For European organizations, the primary impact of CVE-2025-47729 is the potential exposure of sensitive communications stored in the TeleMessage archiving backend. This exposure could lead to breaches of confidentiality, violating data protection regulations such as the GDPR, which mandates strict controls over personal and sensitive data. Organizations in sectors like finance, healthcare, legal, and government that rely on TeleMessage for secure messaging and archiving may face compliance risks and reputational damage if message contents are accessed without authorization. Although the vulnerability requires high privileges and local access, insider threats or compromised administrative accounts could exploit this to extract cleartext messages. The lack of end-to-end encryption in practice undermines trust in the platform’s security claims, potentially leading to loss of customer confidence and legal liabilities. The impact on integrity and availability is negligible, but confidentiality breaches alone can have severe consequences in regulated environments. The absence of known exploits reduces immediate risk, but the hidden nature of the functionality suggests a need for urgent review and remediation.

European organizations using TeleMessage archiving backend should take the following specific steps: 1) Conduct a thorough audit of the archiving backend to verify whether messages are stored encrypted at rest and if any cleartext copies exist. 2) Restrict and monitor administrative and backend access tightly to minimize the risk of insider threats or unauthorized access. 3) Engage with TeleMessage to obtain official clarification and request patches or configuration options that enforce true end-to-end encryption through to the archive. 4) Implement additional encryption layers or data protection controls on archived data if vendor fixes are delayed. 5) Review and update data handling and compliance policies to reflect the actual security posture of the messaging system. 6) Train security teams to detect anomalous access patterns to the archiving backend that could indicate exploitation attempts. 7) Consider alternative secure messaging solutions if TeleMessage cannot guarantee end-to-end encryption compliance. 8) Maintain up-to-date logging and alerting on backend access to enable rapid incident response. These measures go beyond generic advice by focusing on verifying vendor claims, controlling privileged access, and preparing for potential compliance audits.