Tuesday 3 November
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Security timeline

  1. Named in breach reports by Cyber Security NewsAttackers impersonate IT help desks on Microsoft Teams to gain remote access and abuse certificate services
  2. Named in breach reports by The Hacker NewsAttackers posing as IT support on Teams abused AD CS to obtain privileged certificates
  3. Activity reported by GBHackersHackers impersonate IT help desk on Microsoft Teams to gain domain admin via AD CS attacks
  4. Activity reported by Microsoft Security BlogTeams help desk impersonation leads to AD CS ESC1 and ESC8 certificate abuse in two intrusions

Recent news

Cyber Security News· · High

Attackers impersonate IT help desks on Microsoft Teams to gain remote access and abuse certificate services

Microsoft investigated two intrusions in which attackers impersonated help desk staff via Teams chats and calls and got users to approve Quick Assist remote-support sessions. The attackers dropped portable Python, Bun or Java runtimes and staged scripts, then abused weak configurations to obtain certificates for privileged accounts. In one case an excluded privileged account was used to exfiltrate files with Rclone to an external SFTP server, and blocked over 1,000 subsequent SMB file-access attempts.

The Hacker News· · High

Attackers posing as IT support on Teams abused AD CS to obtain privileged certificates

Attackers impersonated IT support over to persuade employees to grant remote control of their PCs. They then exploited insecure (AD CS) configurations to obtain login certificates for privileged accounts, including a domain controller. Microsoft reported investigating two such intrusions, one of which resulted in company data being stolen; the excerpt is truncated.

GBHackers· · High

Hackers impersonate IT help desk on Microsoft Teams to gain domain admin via AD CS attacks

Attackers impersonated IT help desk staff on to obtain remote access, then abused to turn support sessions into privileged authentication paths. Microsoft disclosed two intrusions on October 30, 2026, involving certificate template abuse and NTLM relay. The attacks did not exploit a Teams vulnerability.

Microsoft Security Blog· · High

Teams help desk impersonation leads to AD CS ESC1 and ESC8 certificate abuse in two intrusions

Threat Intelligence investigated two human-operated intrusions that began with Teams messages and calls impersonating help desk staff, leading users to approve Quick Assist sessions. The attackers staged portable Python, or Java runtimes, performed discovery and probed AD CS. In Case 1 an ESC1-vulnerable template gave certificates for privileged accounts and DCSync. In Case 2 PetitPotam and an ESC8 relay gave a domain controller certificate.