My outlook account notices some unusual IMAP Login from Microsoft at Redmond

Anonymous
2022-07-12T08:27:40+00:00

I'm noticed from Microsoft Account Service that my outlook account has been exposed some IMAP Logins from each of the IPv4 addresses at 13.101.0.0-13.101.255.255 since 2022-07-11 JST informed as "unusual activity".

And I found with using whois service that these IP may be managed by Microsoft and placed at Redmond city in US.

Yeah I changed PW in usual way but these access can't stop anyway, so I'm guessing this is a specification for Outlook service.

But at the same time I am afraid of some attacks to Outlook service or Microsoft's collection of users data.

Does Anyone know some information about these kinds of access?

I already used technical help service of online chats in Japan, but he said that he doesn't have some clear idea.

Notification

Thanks to any users to read this thread and report the same issue.

I guess you all are as anxious as I am, but I'd like you to just keep focus on the topic of "unusual activity" from 13.101.0.0/16 here.

While many attacks on login to some system will happen all the time around the world, Thus this case is unique in that it's coming from IPv4 addresses inside Microsoft.

And here we hope to solve this strange problem.

Thank you for your cooperation.

S.E.

Outlook | Web | Outlook.com | Account management, security, and privacy

Locked Question. This question was migrated from the Microsoft Support Community. You can vote on whether it's helpful, but you can't add comments or replies or follow the question.

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Anonymous
2022-07-19T22:42:18+00:00

User @Chezlong Just placed this on my forum post

https://answers.microsoft.com/en-us/outlook_com/forum/all/unusual-account-activity-from-ms-ip-addresses/974cc1c1-232f-44a2-b0eb-0f378fd2c801?page=5:

Finally got to talk to someone at MS- this was their reply:

Thank you for the information. Please be advise that Microsoft is aware of this known issue already. This started to happen even last week and we are already working with this matter. We even have created a ticket number for this issue while it is still happening.

The ticket number for the emerging issue is INC31680156.

So they are on it, but no idea when it will be fixed.

[EDIT] They also confirmed that the account was secure, no need to change passwords, etc

AND

Found the following on thread https://answers.microsoft.com/en-us/outlook\_com/forum/all/outlook-mail-account-unusual-activity/6cfb226f-8cd7-41ae-bd0a-a80d100af543?page=9

posted by user @Pierre-LucMorais:

I have looked for other means to communicate to MS and I found an “official” thread to post this problem. Your mile may vary but i’ve had a reply on my thread and encourage ppl to try using them as well ?

https://www.reddit.com/r/microsoft/comments/o22lfc/microsoft\_official\_support\_thread/

They’ve responded that it is a backend accessing the service and a known issue.

Hoping this helps

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Anonymous
2022-07-22T15:39:05+00:00

Outlook email users alerted to suspicious activity from Microsoft-owned IP address—
People turn amateur sleuths to discover that the source of all those sign-ins seems to be in Redmond
https://www.theregister.com/2022/07/21/outlook_sign_ins/
Article has an update at the end:

Updated at 09.33 UTC on 22 July 2022 to add:
Following publication of this article, Microsoft sent us a statement:
"We're working to resolve a configuration issue causing some customers to receive these notifications in error," said a Microsoft spokesperson via email.

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  1. Anonymous
    2022-07-17T16:03:45+00:00

    We have No Response for this thread or abuse report from Microsoft Official Staff until today, as far as I know.

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  2. Anonymous
    2022-07-17T12:11:29+00:00

    Has there been any official response from Microsoft, as to whether these IMAP accesses are coming from them or from an external actor?

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  3. Anonymous
    2022-07-17T05:14:29+00:00

    I noticed two IPs from the US managed to successfully sync from IP: 13.101.39.8, and IP: 13.101.94.81.

    13.101.94.81 has been successful in syncing after several password changes.

    But I noticed that my thunderbird client could still sync when I did NOT update it with the newest password. This was extremely confusing. Modifying the saved password to garbage to test if thunderbird would still sync, it did.

    I had to toggle on and off the thunderbird offline mode to cause thunderbird to fail sync and prompt for login. This means that existing sessions with hotmail IMAP servers are NOT terminated upon password changes on hotmail's end. Which seems crazy to me. So that's probably why the hackers can still sync after password changes, cause they didn't close their own session on their end... and hotmail's IMAP servers didn't terminate existing sessions upon password change.

    I'm using IMAP server: imap-mail.outlook.com

    My brother uses outlook.com's web client exclusively and the google authentication app, checking his logs shows a bunch of unsuccessfully syncs. I'm going to give that authenticator app a try.

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