To do this, change include:spf.protection.outlook.com to include:spf.protection.outlook.de. Great article. On-premises email organizations where you route. All SPF TXT records start with this value, Office 365 Germany, Microsoft Cloud Germany only, On-premises email system. SPF sender verification check fail | our organization sender identity. When Microsoft enabled this feature in 2018, some false positives happened (good messages were marked as bad). In case we decide to activate this option, the result is that each of the incoming E-mails accepted by our Office 365 mail server (EOP), and that include SPF sender verification results of SPF = Fail, will automatically be marked as spam mail. This ASF setting is no longer required. Feb 06 2023 With a soft fail, this will get tagged as spam or suspicious. Some services have other, more strict checks, but few go as far as EOP to block unauthenticated email and treat them as spoofed messages. Messages that contain hyperlinks that redirect to TCP ports other than 80 (HTTP), 8080 (alternate HTTP), or 443 (HTTPS) are marked as spam. For example, let's say that your custom domain contoso.com uses Office 365. One option that is relevant for our subject is the option named SPF record: hard fail. This type of scenario, there is a high chance that we are experiencing a Spoof mail attack! Misconception 3: In Office 365 and Exchange Online based environment the SPF protection mechanism is automatically activated. For more information, see Configure anti-spam policies in EOP. Set Up SPF Record Office 365 to Prevent Spoofing and - DuoCircle In Office 365 based environment (Exchange Online and EOP) beside the option of using Exchange rule, we can use an additional option the spam filter policy. Most of the time, I dont recommend executing a response such as block and delete E-mail that was classified as spoofing mail because the simple reason is that probably we will never have full certainty that the specific E-mail message is indeed spoofed mail. office 365 mail SPF Fail but still delivered - Microsoft Community Hub Microsoft Office 365. Sender Policy Framework (SPF) allows email administrators to reduce sender-address forgery (spoofing) by specifying which are allowed to send email for a domain. The main purpose of SPF is to serve as a solution for two main scenarios: A Spoof mail attacks scenario, in which hostile element abuses our organizational identity, by sending a spoofed E-mail message to external recipients, using our organizational identity (our domain name). Did you know you can try the features in Microsoft 365 Defender for Office 365 Plan 2 for free? Basically, SPF, along with DKIM, DMARC, and other technologies supported by Office 365, help prevent spoofing and phishing. For example, in case that we need to Impose a strict security policy, we will not be willing to take the risk, and in such scenario, we will block the E-mail message, send the E-mail to quarantine or forward the E-mail to a designated person that will need to examine the E-mail and decide if he wants to release the E-mail or not. You can read a detailed explanation of how SPF works here. This is the default value, and we recommend that you don't change it. Attackers will adapt to use other techniques (for example, compromised accounts or accounts in free email services). This is the main reason for me writing the current article series. The SPF Fail policy article series included the following three articles: Q1: How does the Spoof mail attack is implemented? Setting up SPF in Office 365 means you need to create an SPF record that specifies all your legitimate outgoing email hosts, and publish it in the DNS. Enabling one or more of the ASF settings is an aggressive approach to spam filtering. The reason for the outcome of SPF = Fail is related to a missing configuration on the sending mail infrastructure., The E-mail address of the sender, uses the domain name of, The result from the SPF sender verification test is , The popular organization users who are being attacked, The various types of Spoofing or Phishing attacks, The E-mail address of the sender includes our domain name (in our specific scenario; the domain name is, The result of the SPF sender verification check is fail (SPF = Fail). You need all three in a valid SPF TXT record. Q3: What is the purpose of the SPF mechanism? Received-SPF: Fail (protection.outlook.com: domain of mydomain.com does not designate 67.220.184.98 as permitted sender) receiver=protection.outlook.com; why spffailed mails normally received? Office 365: Conditional Sender ID Filtering: Hard fail is ON Otherwise, use -all. The responsibility of what to do in a particular SPF scenario is our responsibility! Domain administrators publish SPF information in TXT records in DNS. Most of the mail infrastructures will leave this responsibility to us meaning the mail server administrator. In this article, I am going to explain how to create an Office 365 SPF record. Read the article Create DNS records at any DNS hosting provider for Microsoft 365 for detailed information about usage of Sender Policy Framework with your custom domain in Microsoft 365. Messages that hard fail a conditional Sender ID check are marked as spam. The SPF TXT record for Office 365 will be made in external DNS for any custom domains or subdomains. Sender Policy Framework or SPF decides if a sender is authorized to send emails for any domain. SPF Record Contains a Soft Fail - Help Center How to Set Up Microsoft Office 365 SPF record? - PowerDMARC SPF records: Hard Fail vs Soft Fail? - cPanel In order to protect against these, once you have set up SPF, you should also configure DKIM and DMARC for Microsoft 365. However, your risk will be higher. The second one reads the "Authentication-Results" line in the header information and if it says "Fail" sends the email to quarantine. In case you wonder why I use the term high chance instead of definite chance is because, in reality, there is never 100% certainty scenario. This is where we use the learning/inspection mode phase and use it as a radar that helps us to locate anomalies and other infrastructure security issues. The E-mail is a legitimate E-mail message. This defines the TXT record as an SPF TXT record. DMARC email authentication's goal is to make sure that SPF and DKIM information matches the From address. In reality, there is always a chance that the E-mail message in which the sender uses our domain name includes and the result from the SPF sender verification test is Fail could be related to some miss configuration issue. How Sender Policy Framework (SPF) prevents spoofing - Office 365 Test mode is not available for the following ASF settings: Microsoft 365 organizations with Exchange Online mailboxes. Vs. this scenario, in a situation in which the sender E-mail address includes our domain name, and also the result from the SPF sender verification test is fail, this is a very clear sign of the fact that the particular E-mail message has a very high chance to consider as Spoof mail. By analyzing the information thats collected, we can achieve the following objectives: 1. In this step, we want to protect our users from Spoof mail attack. In this scenario, our mail server accepts a request to deliver an email message to one of our organization recipients. In reality, we can never be sure in 100%, that the E-mail message is indeed spoofed E-mail message or, a legitimate E-mail message. The decision regarding the question, how to relate to a scenario in which the SPF results define as None and Fail is not so simple. Outlook.com might then mark the message as spam. To be able to use the SPF option we will need to implement by ourselves the following proceeds: Add to the DNS server that hosts our domain name the required SPF record, and verifies that the syntax of the SPF record is correct + verify that the SPF record includes information about all the entities that send an E-mail message on behalf of our domain name. Jun 26 2020 Also, if you're only using SPF, that is, you aren't using DMARC or DKIM, you should use the -all qualifier. When you want to use your own domain name in Office 365 you will need to create an SPF record. This conception is partially correct because of two reasons: Misconception 2: SPF mechanism was built for identifying an event of incoming mail, in which the sender Spoof his identity, and as a response, react to this event and block the specific E-mail message. If you've already set up mail for Office 365, then you have already included Microsoft's messaging servers in DNS as an SPF TXT record. For example: Previously, you had to add a different SPF TXT record to your custom domain if you were using SharePoint Online. Why is SPF Check Failing with Office 365 - Spambrella However, because anti-spoofing is based upon the From address in combination with the MAIL FROM or DKIM-signing domain (or other signals), it's not enough to prevent SRS forwarded email from being marked as spoofed. Take a look at the basic syntax for an SPF rule: For example, let's say the following SPF rule exists for contoso.com: v=spf1 . To get started, see Use DKIM to validate outbound email sent from your custom domain in Microsoft 365. A2: The purpose of using the identity of one of our organization users is because, there is a high chance that the Innocent victim (our organization user), will tend to believe someone he knows vs. some sender that he doesnt know (and for this reason tends to trust less). While there was disruption at first, it gradually declined. We don't recommend that you use this qualifier in your live deployment. How To Avoid SPF Validation Error Office 365 - DuoCircle Given that the SPF record is configured correctly, and given that the SPF record includes information about all of our organizations mail server entities, there is no reason for a scenario in which a sender E-mail address which includes our domain name will mark by the SPF sender verification test as Fail.