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. For instructions, see Gather the information you need to create Office 365 DNS records. All SPF TXT records end with this value. For advanced examples, a more detailed discussion about supported SPF syntax, spoofing, troubleshooting, and how Office 365 supports SPF, see How SPF works to prevent spoofing and phishing in Office 365. When it finds an SPF record, it scans the list of authorized addresses for the record. All SPF TXT records start with this value, Office 365 Germany, Microsoft Cloud Germany only, On-premises email system. In scenario 1, in which the sender uses the identity of a well-known organization, we can never be sure definitively that the E-mail message is indeed a spoofed E-mail. If you go over that limit with your include, a-records an more, mxtoolbox will show up an error! You will also need to watch out for the condition where you SPF record contains more than 10 DNS lookups, and take action to fix it when it happens. Fix Your SPF Errors Now SPF Check Path The path for the check is as follows Exchange Admin Center > Protection > Spam Filter > Double Click Default > Advanced Options > Set SPF record: Hard fail: Off One of the prime reasons why Office 365 produces a validation error is an invalid SPF record. If the receiving server finds out that the message comes from a server other than the Office 365 messaging servers listed in the SPF record, the receiving mail server can choose to reject the message as spam. Based on your mentioned description about "SPF authentication fails for our outbound emails sent by Exchange Online despite having this DNS record : v=spf1 include:spf.protection.outlook.com -all", once could you please provide us your detailed error message screenshot, your SPF record and domain via private message? 01:13 AM Use trusted ARC Senders for legitimate mailflows. These are added to the SPF TXT record as "include" statements. Figure out what enforcement rule you want to use for your SPF TXT record. The only thing that we can do is enable other organizations that receive an email message that has our domain name, the ability to verify if the E-mail is a legitimate E-mail message or not. In the current article, I want to provide you with a useful way, to implement a mail security policy related to an event in which the result of the SPF sender verification check is Fail. If we want to be more precise, an event in which the SPF sender verification test result is Fail, and the sender used the E-mail address, which includes our domain name. An SPF TXT record is a DNS record that helps prevent spoofing and phishing by verifying the domain name from which email messages are sent. Instead, ensure that you use TXT records in DNS to publish your SPF information. LazyAdmin.nl is compensated for referring traffic and business to these companies at no expense to you. In some cases, like the salesforce.com example, you have to use the domain in your SPF TXT record, but in other cases, the third-party may have already created a subdomain for you to use for this purpose. Microsoft suggests that the SPF of Spambrella gets added to the domain's SPF. With a soft fail, this will get tagged as spam or suspicious. 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. In the next two articles (Implementing SPF Fail policy using Exchange Online rule (dealing with Spoof E-mail attack) | Phase 1 learning mode | Part 2#3 and Implementing SPF Fail policy using Exchange Online rule (dealing with Spoof E-mail attack) | Phase 2 production | part 3#3), we will review in details the implementation of SPF fail policy by using an Exchange Online rule. IT, Office365, Smart Home, PowerShell and Blogging Tips. One option that is relevant for our subject is the option named SPF record: hard fail. Office 365 supports only one SPF record (a TXT record that defines SPF) for your domain. SPF sender verification test fail | External sender identity. 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. Upgrade to Microsoft Edge to take advantage of the latest features, security updates, and technical support. 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. Go to your messaging server(s) and find out the External IP addresses (needed from all on-premises messaging servers). A wildcard SPF record (*.) In the following section, I like to review the three major values that we get from the SPF sender verification test. You will first need to identify these systems because if you dont include them in the SPF record, mail sent from those systems will be listed as spam. SPF helps validate outbound email sent from your custom domain (is coming from who it says it is). If you have a custom domain or are using on-premises Exchange servers along with Microsoft 365, you need to manually set up DMARC for your outbound mail. For example, if you are hosted entirely in Office 365 Germany, that is, you have no on-premises mail servers, your SPF TXT record would include rows 1, 4, and 7 and would look like this: If you're already deployed in Office 365 and have set up your SPF TXT records for your custom domain, and you're migrating to Office 365 Germany, you need to update your SPF TXT record. Use the step-by-step instructions for updating SPF (TXT) records for your domain registrar. Other options are: I will give you a couple of examples of SPF records, so you have an idea of how they look when you combine different applications. document.getElementById( "ak_js_1" ).setAttribute( "value", ( new Date() ).getTime() ); LazyAdmin.nl is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com. We do not recommend disabling anti-spoofing protection. Your email address will not be published. Email advertisements often include this tag to solicit information from the recipient. Soft fail. For example, suppose the user at woodgrovebank.com has set up a forwarding rule to send all email to an outlook.com account: The message originally passes the SPF check at woodgrovebank.com but it fails the SPF check at outlook.com because IP #25 isn't in contoso.com's SPF TXT record. Also, if your custom domain does not have an SPF TXT record, some receiving servers may reject the message outright. As you can see in the screenshot below, Microsoft has already detected an existing SPF record, marking it invalid.We can safely add include:spf.protection.outlook.com to our SPF record.In your DNS Hosting Provider, look up the SPF record, and click edit. Add include:spf.protection.outlook.com before the -all elementSo in this case it would be:v=spf1 ip4:213.14.15.20 include:servers.mcsv.net include:spf.protection.outlook.com -all. and/or whitelist Messagelab (as it will not be listed as permitted sender for the domain you are checking): Office 365 Admin > Exchange admin center > protection > connection filter. The second one reads the "Authentication-Results" line in the header information and if it says "Fail" sends the email to quarantine. While there was disruption at first, it gradually declined. When you have created a new Office 365 tenant and your subscription includes Exchange Online or Teams, then you will need to add a couple of DNS records. In this phase, we are only capturing event in which the E-mail address of the sender uses the domain name of our organization, and also; the result from the SPF sender verification test is Fail. In case the mail server IP address that sends the E-mail on behalf of the sender, doesnt appear as authorized IP address in the SPF record, SPF sender verification test result is Fail. This phase is described as learning mode or inspection mode because the purpose of this step has been just to identify an event of a Spoof mail attack in which the hostile element uses an E-mail address that includes our domain name + Log this information. Follow us on social media and keep up with our latest Technology news. The number of messages that were misidentified as spoofed became negligible for most email paths. 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. We are going to start with looking up the DNS records that Microsoft 365 is expecting and then add the correct SPF record to our DNS hosting provider: First, we are going to check the expected SPF record in the Microsoft 365 Admin center. Here is an example of an SPF record published on domain X, authorizing Office 365 to send emails on its behalf: 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 can only create one SPF TXT record for your custom domain. In other words, using SPF can improve our E-mail reputation. 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. Messages that contain numeric-based URLs (typically, IP addresses) are marked as spam. For example, Exchange Online Protection plus another email system. For example, in an Exchange Online based environment, we can activate an Exchange Online server setting that will mark each E-mail message that didnt pass the SPF verification test (SPF = fail) as spam mail. 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. However, anti-phishing protection works much better to detect these other types of phishing methods. Test mode is not available for this setting. To defend against these, once you've set up SPF, you should configure DKIM and DMARC for Office 365. Text. A8: The responsibility of the SPF mechanism is to stamp the E-mail message with the SPF sender verification test results. Feb 06 2023 Received-SPF: Fail ( protection.outlook.com: domain of ourdomain1.com does not designate X .X.X.X as permitted sender) We have SPF for our domain v=spf1 include:spf.protection.outlook.com -all We have also enable that fail SPF email should not get in our admin centre. I always try to make my reviews, articles and how-to's, unbiased, complete and based on my own expierence. This is reserved for testing purposes and is rarely used. You add an SPF TXT record that lists the Office 365 messaging servers as legitimate mail servers for your domain. 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. 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. ASF specifically targets these properties because they're commonly found in spam. TechCommunityAPIAdmin. However, your risk will be higher. There is no right answer or a definite answer that will instruct us what to do in such scenarios. 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. Messages with no subject, no content in the message body, and no attachments are marked as high confidence spam. Your support helps running this website and I genuinely appreciate it. For example, the company MailChimp has set up servers.mcsv.net. Microsoft maintains a dynamic but non-editable list of words that are associated with potentially offensive messages. You can only have one SPF TXT record for a domain. 0 Likes Reply I am using Cloudflare, if you dont know how to change or add DNS records, then contact your hosting provider. You don't need to configure this setting in the following environments, because legitimate NDRs are delivered, and backscatter is marked as spam: In standalone EOP environments that protect inbound email to on-premises mailboxes, turning this setting on or off has the following result: More info about Internet Explorer and Microsoft Edge, Microsoft Defender for Office 365 plan 1 and plan 2. In this scenario, we can choose from a variety of possible reactions.. There are many free, online tools available that you can use to view the contents of your SPF TXT record. We don't recommend that you use this qualifier in your live deployment. This type of mail threat appears in two flavors: In this section, I would like to review a couple of popular misconceptions that relate to the SPF standard. What is the recommended reaction to such a scenario? Disable SPF Check On Office 365. For a list of domain names you should include for Microsoft 365, see External DNS records required for SPF. The following Mark as spam ASF settings set the SCL of detected messages to 6, which corresponds to a Spam filter verdict and the corresponding action in anti-spam policies. In this example, the SPF rule instructs the receiving email server to only accept mail from these IP addresses for the domain contoso.com: This SPF rule tells the receiving email server that if a message comes from contoso.com, but not from one of these three IP addresses, the receiving server should apply the enforcement rule to the message. To fix this issue, a sender rewriting scheme is being rolled out in Office 365 that will change the sender email address to use the domain of the tenant whose mailbox is forwarding the message. If you still like to have a custom DNS records to route traffic to services from other providers after the office 365 migration, then create an SPF record for . 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! Instead of immediately deleting such E-mail items, the preferred option is to redirect this E-mail to some isolated store such as quarantine. The -all rule is recommended. For example: Having trouble with your SPF TXT record? For more information, see Example: SPF TXT record for multiple outbound on-premises mail servers and Microsoft 365. domain name is the domain you want to add as a legitimate sender. Specifically, the Mail From field that . Microsoft Office 365. 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. For example, one of the most popular reasons for the result fail when using the SPF sender verification test is a problem or a miss configuration, in which the IP address of one of our mail server/services that our organization use, was not added to the SPF record. The Exchange rule includes three main parts: In our specific scenario, we will use the Exchange rule using the following configuration setting-, Phase 1. Q8: Who is the element which is responsible for alerting users regarding a scenario in which the result of the SPF sender verification test is Fail? 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. Basically, SPF, along with DKIM, DMARC, and other technologies supported by Office 365, help prevent spoofing and phishing. A soft fail would look like this: v=spf1 ip4 192.xx.xx.xx ~all Q9: So how can I activate the option to capture events of an E-mail message that have the value of SPF = Fail? 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 . If you're already familiar with SPF, or you have a simple deployment, and just need to know what to include in your SPF TXT record in DNS for Microsoft 365, you can go to Set up SPF in Microsoft 365 to help prevent spoofing. To be able to send mail from Office 365 with your own domain name you will need to have SPF configured. SPF enables receiving mail servers to authenticate whether an email message was sent from an authorized mail server - but only when the domain owner's SPF record is valid. Once you've formed your record, you need to update the record at your domain registrar. We recommend that you use always this qualifier. 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. The E-mail message is a spoofed E-mail message that poses a risk of attacking our organization users. More info about Internet Explorer and Microsoft Edge, Microsoft Defender for Office 365 plan 1 and plan 2, You don't know all sources for your email, Advanced Spam Filter (ASF) settings in EOP. For example: Previously, you had to add a different SPF TXT record to your custom domain if you were using SharePoint Online. To work around this problem, use SPF with other email authentication methods such as DKIM and DMARC. When you want to use your own domain name in Office 365 you will need to create an SPF 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). Implement the SPF Fail policy using a two-phase procedure the learning/inspection phase and the production phase. Learn about who can sign up and trial terms here. This will avoid the rejections taking place by some email servers with strict settings for their SPF checks. 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. After a specific period, which we allocate for examining the information that collected, we can move on to the active phase, in which we execute a specific action in a scenario that the Exchange rule identifies an E-mail message that is probably Spoof mail. Sharing best practices for building any app with .NET. However, the industry is becoming more aware about issues with unauthenticated email, particularly because of the problem of phishing. One drawback of SPF is that it doesn't work when an email has been forwarded. So only the listed mail servers are allowed to send mail, A domain name that is allowed to send mail on behalf of your domain, Ip address that is allowed sending mail on behalf of your domain, ip4:21.22.23.24 or complete range: ip4:20.30.40.0/19, Indicates what to do with mail that fails, Sending mail for on-premise systems public IP Address 213.14.15.20, Sending mail from MailChimp (newsletters service). The simple truth is that we cannot prevent this scenario because we will never be able to have control over the external mail infrastructure that is used by these hostile elements. In all Microsoft 365 organizations, the Advanced Spam Filter (ASF) settings in anti-spam policies in EOP allow admins to mark messages as spam based on specific message properties. This change should reduce the risk of SharePoint Online notification messages ending up in the Junk Email folder. Links to instructions on working with your domain registrar to publish your record to DNS are also provided. Neutral. It can take a couple of minutes up to 24 hours before the change is applied. The reason for our confidence that the particular E-mail message has a very high chance to consider as Spoof mail is because we are the authority who is responsible for managing our mail infrastructure. SPF record types were deprecated by the Internet Engineering Task Force (IETF) in 2014. Although there are other syntax options that are not mentioned here, these are the most commonly used options. Need help with adding the SPF TXT record? This setting combines an SPF check with a Sender ID check to help protect against message headers that contain forged senders. This option combines an SPF check with a Sender ID check to help protect against message headers that contain forged senders. It doesn't have the support of Microsoft Outlook and Office 365, though. For example, let's say that your custom domain contoso.com uses Office 365. Despite that the first association regarding the right response to an event in which the sender uses an E-mail address that includes our organization domain name + the result from the SPF sender verification test is fail, is to block and delete such E-mails; I strongly recommend not doing so. 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). Some bulk mail providers have set up subdomains to use for their customers. Misconception 1: Using SPF will protect our organization from every scenario in which hostile element abuses our organizational identity. A3: To improve the ability of our mail infrastructure, to recognize the event in which there is a high chance, that the sender spoofs his identity or a scenario in which we cannot verify the sender identity.The other purpose of the SPF is to protect our domain mane reputation by enabling another organization to verify the identity of an E-mail message that was sent by our legitimate users. Conditional Sender ID filtering: hard fail. This article describes how to update a Domain Name Service (DNS) record so that you can use Sender Policy Framework (SPF) email authentication with your custom domain in Office 365. A typical SPF TXT record for Microsoft 365 has the following syntax: text v=spf1 [<ip4>|<ip6>:<IP address>] [include:<domain name>] <enforcement rule> For example: text v=spf1 ip4:192.168..1 ip4:192.168..2 include:spf.protection.outlook.com -all where: v=spf1 is required. 04:08 AM Outlook.com might then mark the message as spam. It's a first step in setting up the full recommended email authentication methods of SPF, DKIM, and DMARC. These tags are used in email messages to format the page for displaying text or graphics. 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. In the current article series, our primary focus will be how to implement an SPF policy for incoming mail, by using the option of Exchange rule, and not by using the Exchange Online spam filter policy option. Despite my preference for using Exchange rule as preferred tool for enforcing the required SPF policy, I would also like to mention an option that is available for Office 365 customers, which their mail infrastructure based on Exchange Online and EOP (Exchange Online Protection). In order to use a custom domain, Office 365 requires that you add a Sender Policy Framework (SPF) TXT record to your DNS record to help prevent spoofing. Destination email systems verify that messages originate from authorized outbound email servers. You can list multiple outbound mail servers. Select 'This page' under 'Feedback' if you have feedback on this documentation. If you're the sender's email admin, make sure the SPF records for your domain at your domain registrar are set up correctly. 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. DKIM email authentication's goal is to prove the contents of the mail haven't been tampered with. My opinion that blocking or rejecting such E-mail messages is too risky because, we cannot enforce other organizations to use SPF, although using SPF is recommended and help to protect the identity and the reputation of a particular domain. 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. From my experience, the phase is fascinating because after we activate the monitor process, we will usually find an absorbing finding of: Based on this information, we will be able to understand the real scope of the problem, the main characters of this attack and so on. In reality, the recipient will rarely access data stored in the E-mail message header, and even if they access the data, they dont have the ability to understand most of the information thats contained within the E-mail header. Indicates neutral. For example, create one record for contoso.com and another record for bulkmail.contoso.com. For example, 131.107.2.200. Did you know you can try the features in Microsoft 365 Defender for Office 365 Plan 2 for free? SPF is configured by adding a specially formatted TXT record to the DNS zone for the domain. Include the following domain name: spf.protection.outlook.com. Best thing to do is report the message via the Junk add-in and open a support case to have it properly investigated. In this step, we want to protect our users from Spoof mail attack. If you don't use a custom URL (and the URL used for Office 365 ends in onmicrosoft.com), SPF has already been set up for you in the Office 365 service. You can't report messages that are filtered by ASF as false positives. Sender Policy Framework or SPF decides if a sender is authorized to send emails for any domain. Customers on US DC (US1, US2, US3, US4 . What are the possible options for the SPF test results? is required for every domain and subdomain to prevent attackers from sending email claiming to be from non-existent subdomains.