Gather this information: The SPF TXT record for your custom domain, if one exists. For example, at the time of this writing, Salesforce.com contains 5 include statements in its record: To avoid the error, you can implement a policy where anyone sending bulk email, for example, has to use a subdomain specifically for this purpose. Getting Started with PDQ Deploy & Inventory, Automatically assign licenses in Office 365, Match all domain name records (A and AAAA), Match all listed MX records. 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. Attackers will adapt to use other techniques (for example, compromised accounts or accounts in free email services). In case that your organization experiences a scenario in which your mail server IP address, In the current article and the next article: My E-mail appears as spam | Troubleshooting, In the current article, we will review how to deal with Spoof mail by creating, Your email address will not be published. Use trusted ARC Senders for legitimate mailflows. This article provides frequently asked questions and answers about anti-spoofing protection for Microsoft 365 organizations with mailboxes in Exchange Online, or standalone Exchange Online Protection (EOP) organizations without Exchange Online mailboxes. This is the scenario in which we get a clear answer regarding the result from the SPF sender verification test the SPF test fail! Authentication-Results: spf=none (sender IP is 118.69.226.171) smtp.mailfrom=kien.ngan; thakrale5.onmicrosoft.com; dkim=none (message not signed) header.d=none;thakrale5.onmicrosoft.com; dmarc=none action=none header.from=thakrale5.onmicrosoft.com; Received-SPF: None (protection.outlook.com: kien.ngan does not designate permitted sender hosts) The meaning is a hostile element that executes spoofing or Phishing attacks and uses a sender E-mail address that includes our domain name. Creating multiple records causes a round robin situation and SPF will fail. The rest of this article uses the term SPF TXT record for clarity. In each of the above scenarios, the event in which the SPF sender verification test ended with SPF = Fail result is not good. 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. Default value - '0'. You need some information to make the record. Unfortunately, no. SPF (Sender Policy Framework) is an email authorization protocol that checks the sender's IP address against a list of IPs published on the domain used as the Return-Path header of the email sent. For advanced examples and a more detailed discussion about supported SPF syntax, see How SPF works to prevent spoofing and phishing in Office 365. More info about Internet Explorer and Microsoft Edge. GoDaddy, Bluehost, web.com) & ask for help with DNS configuration of SPF (and any other email authentication method). In this category, we can put every event in which a legitimate E-mail message includes the value of SPF = Fail. A5: The information is stored in the E-mail header. Follow us on social media and keep up with our latest Technology news. 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. Learning/inspection mode | Exchange rule setting. Keeping track of this number will help prevent messages sent from your organization from triggering a permanent error, called a perm error, from the receiving server. If you set up mail when you set up Microsoft 365, you already created an SPF TXT record that identifies the Microsoft messaging servers as a legitimate source of mail for your domain. Although SPF is designed to help prevent spoofing, but there are spoofing techniques that SPF can't protect against. What is SPF? This tag allows the embedding of different kinds of documents in an HTML document (for example, sounds, videos, or pictures). The SPF TXT record for Office 365 will be made in external DNS for any custom domains or subdomains. For example, let's say that your custom domain contoso.com uses Office 365. Upgrade to Microsoft Edge to take advantage of the latest features, security updates, and technical support. This ASF setting is no longer required. It doesn't have the support of Microsoft Outlook and Office 365, though. Messages that hard fail a conditional Sender ID check are marked as spam. is the domain of the third-party email system. By looking at your SPF TXT record and following the chain of include statements and redirects, you can determine how many DNS lookups the record requires. Notify me of followup comments via e-mail. It is published as a Domain Name System (DNS) record for that domain in the form of a specially formatted TXT record. 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. If you are a small business, or are unfamiliar with IP addresses or DNS configuration, call your Internet domain registrar (ex. 04:08 AM SPF record types were deprecated by the Internet Engineering Task Force (IETF) in 2014. Microsoft believes that the risk of continuing to allow unauthenticated inbound email is higher than the risk of losing legitimate inbound email. 0 Likes Reply Also, the original destination recipient will get an E-mail notification, which informs him that a specific E-mail message that was sent to him was identified as Spoof mail and for this reason didnt automatically send to his mailbox. This tag is used to create website forms. In the next article, Implementing SPF Fail policy using Exchange Online rule (dealing with Spoof E-mail attack) | Phase 1 learning mode | Part 2#3, we will review the step-by-step instruction needed to create an Exchange Online rule that will help us to monitor such events. Failing SPF will not cause Office 365 to drop a message, at best it will mark it as Junk, but even that wont happen in all scenarios. Make sure that you include all mail systems in your SPF record, otherwise, mail sent from these systems will be listed as spam messages. For questions and answers about anti-malware protection, see Anti-malware protection FAQ. Your email address will not be published. An SPF record is a DNS entry containing the IP addresses of an organization's official email servers and domains that can send emails on behalf of your business. You add an SPF TXT record that lists the Office 365 messaging servers as legitimate mail servers for your domain. How Does An SPF Record Prevent Spoofing In Office 365? For example, we are reasonable for configuring SPF record that will represent our domain and includes the information about all the mail server (the Hostname or the IP address) that can send E-mail on behalf of our domain name. is required for every domain and subdomain to prevent attackers from sending email claiming to be from non-existent subdomains. In simple words, the destination recipient is not aware of a scenario in which the SPF result is Fail, and they are not aware of the fact that the E-mail message could be a spoofed E-mail. Upgrade to Microsoft Edge to take advantage of the latest features, security updates, and technical support. You can only have one SPF TXT record for a domain. SPF works best when the path from sender to receiver is direct, for example: When woodgrovebank.com receives the message, if IP address #1 is in the SPF TXT record for contoso.com, the message passes the SPF check and is authenticated. If you have a hybrid configuration (some mailboxes in the cloud, and some mailboxes on premises) or if you're an Exchange Online Protection standalone customer, add the outbound IP address of . Keep in mind, that SPF has a maximum of 10 DNS lookups. A8: The responsibility of the SPF mechanism is to stamp the E-mail message with the SPF sender verification test results. This record probably looks like this: If you're a fully hosted customer, that is, you have no on-premises mail servers that send outbound mail, this is the only SPF TXT record that you need to publish for Office 365. This change should reduce the risk of SharePoint Online notification messages ending up in the Junk Email folder. In the following section, I like to review the three major values that we get from the SPF sender verification test. 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). These are added to the SPF TXT record as "include" statements. Instruct the Exchange Online what to do regarding different SPF events.. To defend against these, once you've set up SPF, you should configure DKIM and DMARC for Office 365. The Exchange rule includes three main parts: In our specific scenario, we will use the Exchange rule using the following configuration setting-, Phase 1. A good option could be, implementing the required policy in two phases-. SRS only partially fixes the problem of forwarded email. Implement the SPF Fail policy using a two-phase procedure the learning/inspection phase and the production phase. This is the main reason for me writing the current article series. This defines the TXT record as an SPF TXT record. This option enables us to activate an EOP filter, which will mark incoming E-mail message that has the value of "SFP =Fail" as spam mail (by setting a high SCL value). Required fields are marked *. If you do not use any external third-party email services and route all your emails via Office 365, your SPF record will have the following syntax: v=spf1 include:spf.protection.outlook.com -all. Typically, email servers are configured to deliver these messages anyway. 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. and are the IP address and domain of the other email system that sends mail on behalf of your domain. This ASF setting is no longer required. The SPF mechanism is not responsible for notifying us or, to draw our attention to events in which the result from the SPF sender verification test considered as Fail.. In order to help prevent denial of service attacks, the maximum number of DNS lookups for a single email message is 10. Also, if you're using DMARC with p=quarantine or p=reject, then you can use ~all. 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. To be able to send mail from Office 365 with your own domain name you will need to have SPF configured. Office 365 supports only one SPF record (a TXT record that defines SPF) for your domain. Microsoft itself first adopted the new email authentication requirements several weeks before deploying it to customers. Instead, ensure that you use TXT records in DNS to publish your SPF information. However, if you bought Office 365 Germany, part of Microsoft Cloud Germany, you should use the include statement from line 4 instead of line 2. Auto-suggest helps you quickly narrow down your search results by suggesting possible matches as you type. For questions and answers about anti-spam protection, see Anti-spam protection FAQ. One option that is relevant for our subject is the option named SPF record: hard fail. A scenario in which hostile element spoofs the identity of a legitimate recipient, and tries to attack our organization users. While there was disruption at first, it gradually declined. We reviewed the need for completing the missing part of our SPF implementation, in which we need to capture an event of SPF sender verification test in which the result is fail and, especially, in a scenario in which the sender E-mail address includes our domain name (most likely certainly a sign that this is a Spoof mail attack). Use the 90-day Defender for Office 365 trial at the Microsoft 365 Defender portal trials hub. To do this, contoso.com publishes an SPF TXT record that looks like this: When the receiving server sees this record in DNS, it also performs a DNS lookup on the SPF TXT record for contoso.net and then for contoso.org. Learn about who can sign up and trial terms here. DKIM email authentication's goal is to prove the contents of the mail haven't been tampered with. Summary: This article describes how Microsoft 365 uses the Sender Policy Framework (SPF) TXT record in DNS to ensure that destination email systems trust messages sent from your custom domain. 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. What does SPF email authentication actually do? What happens to the message is determined by the Test mode (TestModeAction) value: The following Increase spam score ASF settings result in an increase in spam score and therefore a higher chance of getting marked as spam with a spam confidence level (SCL) of 5 or 6, which corresponds to a Spam filter verdict and the corresponding action in anti-spam policies. @tsulafirstly, this mostly depends on the spam filtering policy you have configured. Q6: In case that the information in the E-mail message header includes results of SPF = Fail, does the destination recipient is aware of this fact? ip4: ip6: include:. This is no longer required. Setting up DMARC for your custom domain includes these steps: Step 1: Identify valid sources of mail for your domain. Periodic quarantine notifications from spam and high confidence spam filter verdicts. The most important purpose of the learning/inspection mode phase is to help us to locate cracks and grooves in our mail infrastructure. You intend to set up DKIM and DMARC (recommended). Generate and Send an incident report to a designated recipient (shared mailbox) that will include information about the characters of the event + the original E-mail message. Given that we are familiar with the exact structure of our mail infrastructure, and given that we are sure that our SPF record includes the right information about our mail servers IP address, the conclusion is that there is a high chance that the E-mail is indeed spoofed E-mail! This conception is half true. Best thing to do is report the message via the Junk add-in and open a support case to have it properly investigated. In other words, using SPF can improve our E-mail reputation. Use the syntax information in this article to form the SPF TXT record for your custom domain. If you have any questions, just drop a comment below. SPF records in Office 365 are DNS records that help authenticate Office 365 based emails so organizations can operate with higher levels of trust and prevent spoofing. The interesting thing is that in Exchange-based environment, we can use very powerful Exchange server feature named- Exchange rule, for identifying an event in which the SPF sender verification test result is Fail, and define a response respectively. A9: The answer depends on the particular mail server or the mail security gateway that you are using. In these examples, contoso.com is the sender and woodgrovebank.com is the receiver. We recommend the value -all. A hard fail, for example, is going to look like this: v=spf1 ip4 192.xx.xx.xx -all If mail is being sent from another server that's not the IP in the SPF, the receiving server will discard it. After examining the information collected, and implementing the required adjustment, we can move on to the next phase. When you want to use your own domain name in Office 365 you will need to create an SPF record. Can we say that we should automatically block E-mail message which their organization doesnt support the use of SPF? Step 2: Set up SPF for your domain. Did you know you can try the features in Microsoft 365 Defender for Office 365 Plan 2 for free? In this phase, we will need to decide what is the concrete action that will apply for a specific E-mail message that will identify a Spoof mail (SPF = Fail). The meaning of the SPF = Fail is that we cannot trust the mail server that sends the E-mail message on behalf of the sender and for this reason, we cannot trust the sender himself. Another distinct advantage of using Exchange Online is the part which enables us to select a very specific response (action), that will suit our needs such as Perpend the E-mail message subject, Send warning E-mail, send the Spoof mail to quarantine, generate the incident report and so on. This is no longer required. Otherwise, use -all. When this setting is enabled, any message that hard fails a conditional Sender ID check is marked as spam. SPF is added as a TXT record that is used by DNS to identify which mail servers can send mail on behalf of your custom domain. Upgrade to Microsoft Edge to take advantage of the latest features, security updates, and technical support. The SPF mechanism doesnt perform and concrete action by himself. Below is an example of adding the office 365 SPF along with onprem in your public DNS server. If you have anti-spoofing enabled and the SPF record: hard fail ( MarkAsSpamSpfRecordHardFail) turned on, you will probably get more false positives. We . For example: Previously, you had to add a different SPF TXT record to your custom domain if you were using SharePoint Online. By analyzing the information thats collected, we can achieve the following objectives: 1.