TeleMessage TM SGNL Hidden Functionality Vulnerability (CVE-2025-47729)

TeleMessage TM SGNL contains a hidden functionality vulnerability in which the archiving backend holds cleartext copies of messages from TM SGNL application users.

Published May 8, 2025 · Updated May 29, 2026

X LinkedIn

Why patchRisk explained in plain English

Worst-case scenarioIf unpatched

A local attacker, with administrative privileges, can achieve full data confidentiality loss. Federal agencies are required to remediate by 2025-06-02 under CISA BOD 22-01.

How the attack worksNo clicks needed

This is a Software Vulnerability (CWE-912) (CWE-912) vulnerability in TeleMessage TM SGNL. The TeleMessage archiving backend through 2025-05-05 holds cleartext copies of messages from TM SGNL (aka Archive Signal) app users, which is different functionality than described in the TeleMessage "End-to-End encryption from the mobile phone through to the corporate archive" documentation, as exploited in the wild in May 2025. Exploitation requires local access, higher attack complexity, an administrative account, and no user interaction required.

Am I affected?Quick check

Probably yes if any of these apply:

●IT Security

●Running text message archiver: v ≤ 2025-05-05

Real-world incidentsWhat we've seen

Active exploitation documented in the wild. Threat-research write-up: https://arstechnica.com/security/2025/05/signal-clone-used-by-trump-official-stops-operations-after-report-it-was-hacked/

How to patch

Manual remediation steps

Apply the Vendor Patch

This vulnerability is in the CISA Known Exploited Vulnerabilities catalog — apply the vendor's security update as soon as possible.

CISA required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.