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
    2022-07-15T13:52:12+00:00

    That´s an interessting behavior.

    I use Outlook, and for backup purposes I sync mails via IMAP with a linux tool.

    This sync runs every half an hour.

    But those 13.101 sync occurs totally random, I cannot recognize a pattern.

    It also occurs when I stop this cron job.

    Good point, why should Microsoft use IMAP?... I don´t know. But I don´t have unsuccessful accesses since two days.

    It startet two days ago with several unsuccessful access tries, respectively it was like "no, no, yes, no, yes ,yes no"....

    Then a few hours later all access activities were successful and still are despite of password changes.

    If it would be an malicious actor who guessed my password (which btw is pretty unlikely) then it should stop somehow.

    Another point is: how should a malicious actor gain access without further interaction/phishing etc. when 2FA is enabled?

    Very strange!!

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  2. Anonymous
    2022-07-15T14:12:20+00:00

    Another very weird thing I noticed,

    I keep checking my activity every morning when I get up,

    I see attempts at night when Not a single computer is online or accessing the services... so its not ONLY when I use thunderbird...

    As stated before, I do not have any cellphone or anything else other than a single computer accessing my hotmail.com address...

    this morning when I checked, i had 6 un-successful attempts during the night... and 1 successful sync (1 hour ago) *when i only opened the computer about 20mins ago*
    when i clicked "not me, secure your account"
    I got the following :
    You've secured your account since this activity occurred.

    yet i havent changed my password since 2 days ago!!
    And the 20+ previous ones are un-sucessfull sync...
    and 100% of them since this started are always from the same IP
    IP: 13.101.70.247

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  3. Anonymous
    2022-07-15T15:02:56+00:00

    I just want to add that both my husband and I received the "unusual sign-in activity" email for our MSN email accounts. The IP address was 13.101.245.171

    We do not use Thunderbird.

    I didn't think anything of it when my husband received the notice, and he said the IP was in the state of WA - he doesn't use that email for anything, but he changed the PW anyway. Today I received the unusual activity email and when I tracked down the IP to Redmond, WA I knew something was weird since that's the HQ for MS. After googling the issue, I came here and was very interested in everyone's replies!!

    I have not changed my password because I have 2FA set up and the email from MS says "To help keep you safe, we've blocked access to your inbox, contacts list, and calendar for that sign-in." Should I be more concerned?

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