French govt Tchap platform under investigation after breach

French authorities are investigating a significant security breach of Tchap, the government's official messaging platform, after an attacker gained access using a stolen user account. The incident, detected by the national cybersecurity agency ANSSI on Sunday, June 7, has raised concerns about the potential exposure of user data and communications within the public sector.

The investigation, led by the government's digital affairs directorate DINUM, began after a threat actor using the alias "misere" claimed responsibility for the attack over the weekend. The individual alleged they used social engineering to compromise a valid account on the platform's education server. Through this access, the attacker claims to have exfiltrated 13.5 gigabytes of data, including information from 73,467 user accounts, 643,459 messages, and 59,386 shared media files. The individual also alleged accessing discussion rooms involving personnel from multiple ministries and finding hardcoded credentials. These claims have not been independently verified by authorities.

In an official response, DINUM confirmed a security breach involving a hijacked account. The agency stated the malicious account was...