Home windows directors from quite a few organizations report widespread account lockouts triggered by false positives within the rollout of a brand new Microsoft Entra ID’s “leaked credentials” detection app referred to as MACE.
These alerts and lockouts started final night time, with some admins believing they had been false positives because the accounts have distinctive passwords that aren’t used on another websites or purposes.
Microsoft Entra ID, previously Azure Energetic Listing, is a cloud-based identification and entry administration service that helps organizations handle person identities and safe entry to sources.
In a Reddit thread posted early this morning, Home windows admins reported receiving a number of alerts from Entra indicating that a few of their person accounts had been discovered with credentials leaked on the darkish internet or different areas.
These accounts had been mechanically locked out of the tenant, with quite a few customers impacted per group.
“Us as properly… about 1/third of our accounts bought locked out about ~1 hour in the past. We’re a MSP so I am assuming that is occurring to our purchasers as properly,” posted an admin on Reddit.
The locked-out accounts confirmed no indicators of compromise, resembling suspicious sign-ins, and had been protected with MFA. Moreover, breach notification providers like Have I Been Pwned (HIBP) had no matches for these accounts.
One other report on Reddit additional corroborated that this was widespread, with an MDR supplier stating they acquired over 20,000 notifications from Microsoft in a single day relating to leaked credentials from totally different prospects
Whereas Microsoft has not publicly confirmed the reason for these lockouts, Microsoft instructed one of many affected organizations it was brought on by a difficulty with the rollout of a brand new Enterprise software referred to as “MACE Credential Revocation.”
“Simply bought off with engineer. It’s Tenant Lockout because of this MACE ninja rollout they did. no indicators of compromise. He wants an hour to transform the ticket from compromise to lockout however can breathe a sigh of aid. It was Error Code: 53003 for conditional entry coverage,” an admin reported on Reddit.
A number of folks confirmed this software was added to tenants proper earlier than they started receiving the alerts.
MACE Credential Revocation app is a Microsoft Entra function used to detect leaked credentials and lockout doubtlessly compromised accounts.
Whereas all alerts of leaked credentials ought to be investigated to substantiate that an account was not compromised, should you acquired a flurry of alerts directly this rollout doubtless brought about it.
BleepingComputer contacted Microsoft with questions on this incident however has not acquired a response at the moment.
