How attackers get help desk technicians to reset passwords and MFA, and the two controls that stop it from turning into access to every client.
An attacker who can't get past MFA can call your service desk as someone else, usually an executive, an admin or a new hire, and ask a technician to reset the password, reset MFA or add a new MFA device. Two controls deal with it: verify the caller by something they have or can show, not something they know, and make sure any account they take over has no standing admin rights.
Several high-profile intrusions since 2023 started this way, and the method barely changes.
An MSP service desk answers for dozens of client organisations. Technicians rarely know the end users, the SLA rewards closing tickets quickly, and every client's users come in through the same door. A process gap at the MSP is a gap at every client.
MSP technicians also hold the accounts attackers want most. Microsoft notes that Octo Tempest "commonly launches social engineering attacks targeting technical administrators, such as support and help desk personnel." A technician account with standing admin rights across client tenants is the prize, not the side effect.
Date of birth, employee ID, manager's name, the last four digits of anything. Mandiant's 2025 hardening guidance for this threat actor says to avoid relying on publicly available personal data "as UNC3944 often possesses this information." If the caller can recite it, you have confirmed they did their homework, not who they are.
NIST's current authentication guidelines take the same line. None of the account recovery methods they recognise is a knowledge question: they are saved or issued recovery codes, recovery contacts and repeated identity proofing. The same guidelines say verifiers "SHALL NOT" prompt people to use security questions when they choose passwords.
The guidance from Mandiant, Okta and Microsoft points the same way. A procedure that holds up has these parts:
Verify through a known second person, such as the user's manager, using contact details you already hold. Then, in Microsoft Entra ID, issue a Temporary Access Pass rather than setting or reading out a password.
A Temporary Access Pass is a time-limited passcode the user signs in with to register a new authentication method. Its lifetime can be set from 10 minutes to 30 days, and the tenant policy can force one-time use. Keep the lifetime short and use one-time passes for recoveries. Authentication Administrators can issue passes for regular users; issuing one for an admin takes a Privileged Authentication Administrator. The MFA fatigue and MFA reset playbook walks through the Entra steps.
Verification will fail eventually. A technician will be tired, a step will be skipped, a cloned voice will sound right. Plan for the reset that gets through.
What the attacker holds afterwards depends on what that account could do. A regular user account limits the damage to one user. A technician account with standing admin rights across client tenants turns one phone call into access to every client.
That is why help desk security belongs in the same conversation as privileged access. Three phases of the PAM journey do most of the work here:
CyberQP's QDesk verifies end users who contact the help desk before a password or MFA reset. The technician sends the request from the ticket or while on the phone, and the user either approves it in the CyberQP mobile app, Microsoft Authenticator or Duo, or reads back a code sent to them by SMS or email. Help desk identity verification is coming to Panthera; it isn't in Panthera yet. In Panthera today, technicians can work from dedicated just-in-time accounts that are disabled by default, can require a second approval and can be tied to a ConnectWise Manage ticket, and changes to privileged accounts show up in Panthera's event log and auditing alerts.
An attacker contacts the service desk while impersonating a user and persuades a technician to reset a password, reset or add an MFA method, or grant access. It targets the process, not the software.
According to CISA's advisory on the group, it convinced IT help desk staff to reset passwords and MFA tokens, posed as IT staff to get credentials from employees, and used SIM swapping and repeated MFA prompts. Microsoft and Mandiant describe the same pattern.
No. The answers are usually available online or in breach data, and attackers research them before calling. Use something the real user has or can show.
Verify through a known second person using contact details you already hold and a call you start. Then issue a short, one-time Temporary Access Pass so the user can register a new method.
Yes. It doesn't stop the reset, but it limits what the attacker gets. If admin accounts are disabled until a task needs them, a stolen everyday account carries no admin rights.
Sources: CISA AA23-320A, Scattered Spider (16 Nov 2023); Mandiant, Defending Against UNC3944 (6 May 2025); Microsoft, Octo Tempest (25 Oct 2023); Microsoft, Protecting customers from Octo Tempest attacks across multiple industries (16 Jul 2025); Okta, cross-tenant impersonation (31 Aug 2023); UK Parliament, Business and Trade Sub-Committee oral evidence, HC 835 (8 Jul 2025); NCSC, Incidents impacting retailers (4 May 2025); Google Threat Intelligence Group, UNC6671 (6 Aug 2026); NIST SP 800-63B-4 (July 2025); Microsoft Learn, Temporary Access Pass.
Related: help desk caller verification: a nine-step procedure, zero standing privilege and the PAM journey, MFA fatigue and MFA reset attacks, QDesk help desk identity verification, start a free trial, book a demo.