Skip to content

Commit 8f4545a

Browse files
committed
Update anti-phishing-policies-about.md
1 parent 110b1e3 commit 8f4545a

File tree

1 file changed

+38
-44
lines changed

1 file changed

+38
-44
lines changed

defender-office-365/anti-phishing-policies-about.md

Lines changed: 38 additions & 44 deletions
Original file line numberDiff line numberDiff line change
@@ -17,7 +17,7 @@ ms.custom:
1717
description: Admins can learn about the anti-phishing policies that are available in Exchange Online Protection (EOP) and Microsoft Defender for Office 365.
1818
ms.service: defender-office-365
1919
search.appverid: met150
20-
ms.date: 07/24/2024
20+
ms.date: 01/07/2025
2121
appliesto:
2222
- ✅ <a href="https://learn.microsoft.com/defender-office-365/eop-about" target="_blank">Exchange Online Protection</a>
2323
- ✅ <a href="https://learn.microsoft.com/defender-office-365/mdo-about#defender-for-office-365-plan-1-vs-plan-2-cheat-sheet" target="_blank">Microsoft Defender for Office 365 Plan 1 and Plan 2</a>
@@ -39,6 +39,18 @@ Examples of Microsoft Defender for Office 365 organizations include:
3939

4040
[!INCLUDE [Security Analyzer setup guide](../includes/security-analyzer-setup-guide.md)]
4141

42+
Anti-phishing policies in EOP and Defender for Office 365 are both available on the **Anti-phishing** page at <https://security.microsoft.com/antiphishing> in the Microsoft Defender portal. However, the key difference lies in the extra layers of protection provided by Defender for Office 365 licenses. While EOP offers essential anti-phishing protection features, Defender for Office 365 enhances these capabilities by including the following advanced protections:
43+
44+
- **Impersonation protection**:
45+
- Protection against user, domain, and sender impersonation.
46+
- Ability to define trusted senders and domains to reduce false positives.
47+
- **Advanced phishing detection**:
48+
- Customizable phishing thresholds to fine-tune detection.
49+
- **AI and machine learning-based detection**:
50+
- Improved detection of sophisticated phishing attacks through advanced algorithms.
51+
- **Additional reporting and insights**:
52+
- Advanced reporting features and visibility into phishing attempts beyond basic logging.
53+
4254
The high-level differences between anti-phishing policies in EOP and anti-phishing policies in Defender for Office 365 are described in the following table:
4355

4456
|Feature|Anti-phishing policies<br>in EOP|Anti-phishing policies<br>in Defender for Office 365|
@@ -51,25 +63,6 @@ The high-level differences between anti-phishing policies in EOP and anti-phishi
5163
|Impersonation settings|||
5264
|Advanced phishing thresholds|||
5365

54-
Both Exchange Online Protection and Defender for Office 365 anti-phishing policies are configured from the same location within the Microsoft 365 Defender portal. However, the key difference lies in the additional layers of protection provided by Defender for Office 365, which are enabled through its licensing. While EOP offers essential anti-phishing protection features, Defender for Office 365 enhances these capabilities by introducing advanced protection mechanisms within the same configuration interface.
55-
56-
**Key Differences Enabled by Defender for Office 365:**
57-
58-
**Impersonation Protection:**
59-
- Protection against user, domain, and sender impersonation.
60-
- Ability to define trusted senders and domains to reduce false positives.
61-
62-
**Advanced Phishing Detection:**
63-
- Customizable phishing thresholds (Standard, Aggressive, Most Aggressive) to fine-tune detection.
64-
65-
**AI and Machine Learning-Based Detection:**
66-
- Improved detection of sophisticated phishing attacks through advanced algorithms.
67-
68-
**Additional Reporting and Insights:**
69-
- Advanced reporting features and visibility into phishing attempts beyond basic logging.
70-
71-
In summary, while both EOP and Defender for Office 365 anti-phishing policies are accessed and configured from the same portal, an Defender for Office 365 license unlocks advanced anti-phishing features and enhanced security layers within the same interface.
72-
7366
<sup>\*</sup> In the default policy, the policy name and description are read-only (the description is blank), and you can't specify who the policy applies to (the default policy applies to all recipients).
7467

7568
To configure anti-phishing policies, see the following articles:
@@ -119,6 +112,9 @@ The following policy settings are available in anti-phishing policies in EOP and
119112

120113
Spoofing is when the From address in an email message (the sender address that's shown in email clients) doesn't match the domain of the email source. For more information about spoofing, see [Anti-spoofing protection in Microsoft 365](anti-phishing-protection-spoofing-about.md).
121114

115+
> [!TIP]
116+
> For a comparison of spoofing versus impersonation, see the [Spoofing vs. impersonation](#spoofing-vs-impersonation) section later in this article.
117+
122118
The following spoof settings are available in anti-phishing policies in EOP and Defender for Office 365:
123119

124120
- **Enable spoof intelligence**: Turns spoof intelligence on or off. We recommend that you leave it turned on.
@@ -220,33 +216,35 @@ Depending on the number of recipients in the message, the first contact safety t
220216
:::image type="content" source="media/safety-tip-first-contact-multiple-recipients.png" alt-text="The First contact safety tip for messages with multiple recipients" lightbox="media/safety-tip-first-contact-multiple-recipients.png":::
221217

222218
> [!NOTE]
223-
> If the message has multiple recipients, whether the tip is shown and to whom is based on a majority model. If the majority of recipients have never or don't often receive messages from the sender, then the affected recipients will receive the **Some people who received this message...** tip. If you're concerned that this behavior exposes the communication habits of one recipient to another, you should not enable the first contact safety tip and continue to use mail flow rules and the **X-MS-Exchange-EnableFirstContactSafetyTip** header instead.
219+
> If the message has multiple recipients, whether the tip is shown and to whom is based on a majority model. If the majority of recipients have never or don't often receive messages from the sender, the affected recipients receive the **Some people who received this message...** tip. If you're concerned that this behavior exposes the communication habits of one recipient to another, you shouldn't enable the first contact safety tip and continue to use mail flow rules and the **X-MS-Exchange-EnableFirstContactSafetyTip** header instead.
224220
>
225-
> The first contact safety tip is not stamped in S/MIME signed messages.
221+
> The first contact safety tip isn't stamped in S/MIME signed messages.
226222
227223
## Exclusive settings in anti-phishing policies in Microsoft Defender for Office 365
228224

229225
This section describes the policy settings that are only available in anti-phishing policies in Defender for Office 365.
230226

231227
> [!NOTE]
232-
> The default anti-phishing policy in Defender for Office 365 provides [spoof protection](anti-phishing-policies-about.md#spoof-settings) and mailbox intelligence for all recipients. However, the other available [impersonation protection](#impersonation-settings-in-anti-phishing-policies-in-microsoft-defender-for-office-365) features and [advanced settings](anti-phishing-policies-about.md#advanced-phishing-thresholds-in-anti-phishing-policies-in-microsoft-defender-for-office-365) are not configured or enabled in the default policy. To enable all protection features, modify the default anti-phishing policy or create additional anti-phishing policies.
228+
> The default anti-phishing policy in Defender for Office 365 provides [spoof protection](anti-phishing-policies-about.md#spoof-settings) and mailbox intelligence for all recipients. However, the other available [impersonation protection](#impersonation-settings-in-anti-phishing-policies-in-microsoft-defender-for-office-365) features and [advanced settings](anti-phishing-policies-about.md#advanced-phishing-thresholds-in-anti-phishing-policies-in-microsoft-defender-for-office-365) aren't configured or enabled in the default policy. To enable all protection features, modify the default anti-phishing policy or create other anti-phishing policies.
233229
234230
### Impersonation settings in anti-phishing policies in Microsoft Defender for Office 365
235231

236232
Impersonation is where the sender or the sender's email domain in a message looks similar to a real sender or domain:
237233

238-
- An example impersonation of the domain contoso.com is ćóntoso.com.
234+
- An example impersonation of the domain `contoso.com` is `ćóntoso.com`.
239235
- User impersonation is the combination of the user's display name and email address. For example, Valeria Barrios ([email protected]) might be impersonated as Valeria Barrios, but with a different email address.
240236

241237
> [!NOTE]
242-
> Impersonation protection looks for domains that are similar. For example, if your domain is contoso.com, we check for different top-level domains (.com, .biz, etc.), but also domains that are even somewhat similar. For example, contosososo.com or contoabcdef.com might be seen as impersonation attempts of contoso.com.
238+
> Impersonation protection looks for domains that are similar. For example, if your domain is contoso.com, we check for different top-level domains (.com, .biz, etc.), but also domains that are even somewhat similar. For example, `contosososo.com` or `contoabcdef.com` might be seen as impersonation attempts of `contoso.com`.
243239
244240
An impersonated domain might otherwise be considered legitimate (the domain is registered, email authentication DNS records are configured, etc.), except the intent of the domain is to deceive recipients.
245241

246242
The impersonation settings described in the following sections are available only in anti-phishing policies in Defender for Office 365.
247243

248244
> [!TIP]
249245
> Details about detected impersonation attempts are available in the impersonation insight. For more information, see [Impersonation insight in Defender for Office 365](anti-phishing-mdo-impersonation-insight.md).
246+
>
247+
> For a comparison of impersonation versus spoofing, see the [Spoofing vs. impersonation](#spoofing-vs-impersonation) section later in this article.
250248
251249
#### User impersonation protection
252250

@@ -257,9 +255,9 @@ You can use protected users to add internal and external sender email addresses
257255
> [!NOTE]
258256
> You can specify a maximum of 350 users for user impersonation protection in each anti-phishing policy.
259257
>
260-
> User impersonation protection does not work if the sender and recipient have previously communicated via email. If the sender and recipient have never communicated via email, the message can be identified as an impersonation attempt.
258+
> User impersonation protection doesn't work if the sender and recipient have previously communicated via email. If the sender and recipient have never communicated via email, the message can be identified as an impersonation attempt.
261259
>
262-
> You might get the error "The email address already exists" if you try to add a user to user impersonation protection when that email address is already specified for user impersonation protection in another anti-phishing policy. This error occurs only in the Defender portal. You won't get the error if you use the corresponding _TargetedUsersToProtect_ parameter in the **New-AntiPhishPolicy** or **Set-AntiPhishPolicy** cmdlets in Exchange Online PowerShell.
260+
> You might get the error "The email address already exists" if you try to add a user to user impersonation protection when that email address is already specified for user impersonation protection in another anti-phishing policy. This error occurs only in the Defender portal. You don't get the error if you use the corresponding _TargetedUsersToProtect_ parameter in the **New-AntiPhishPolicy** or **Set-AntiPhishPolicy** cmdlets in Exchange Online PowerShell.
263261
264262
By default, no sender email addresses are configured for impersonation protection, either in the default policy or in custom policies.
265263

@@ -311,10 +309,10 @@ For detected domain impersonation attempts, the following actions are available:
311309

312310
Mailbox intelligence uses artificial intelligence (AI) to determine user email patterns with their frequent contacts.
313311

314-
For example, Gabriela Laureano ([email protected]) is the CEO of your company, so you add her as a protected sender in the **Enable users to protect** settings of the policy. But, some of the recipients in the policy communicate regularly with a vendor who is also named Gabriela Laureano ([email protected]). Because those recipients have a communication history with [email protected], mailbox intelligence doesn't identify messages from [email protected] as an impersonation attempt of [email protected] for those recipients.
312+
For example, Gabriela Laureano (`[email protected]`) is the CEO of your company, so you add her as a protected sender in the **Enable users to protect** settings of the policy. But, some of the recipients in the policy communicate regularly with a vendor who is also named Gabriela Laureano (`[email protected]`). Because those recipients have a communication history with `[email protected]`, mailbox intelligence doesn't identify messages from `[email protected]` as an impersonation attempt of `[email protected]` for those recipients.
315313

316314
> [!NOTE]
317-
> Mailbox intelligence protection does not work if the sender and recipient have previously communicated via email. If the sender and recipient have never communicated via email, the message can be identified as an impersonation attempt by mailbox intelligence.
315+
> Mailbox intelligence protection doesn't work if the sender and recipient have previously communicated via email. If the sender and recipient have never communicated via email, the message can be identified as an impersonation attempt by mailbox intelligence.
318316
319317
Mailbox intelligence has two specific settings:
320318

@@ -351,14 +349,14 @@ Impersonation safety tips appear to users when messages are identified as impers
351349
> The email address `<email address>` includes unexpected letters or numbers. We recommend you don't interact with this message.
352350
353351
> [!NOTE]
354-
> Safety tips are not stamped in the following messages:
352+
> Safety tips aren't stamped in the following messages:
355353
>
356354
> - S/MIME signed messages.
357355
> - Messages that are allowed by your organizational settings.
358356
359357
#### Trusted senders and domains
360358

361-
Trusted senders and domain are exceptions to the impersonation protection settings. Messages from the specified senders and sender domains are never classified as impersonation-based attacks by the policy. In other words, the action for protected senders, protected domains, or mailbox intelligence protection aren't applied to these trusted senders or sender domains. The maximum limit for these lists is 1024 entries.
359+
Trusted senders and domain are exceptions to the impersonation protection settings. Messages from the specified senders and sender domains are never classified as impersonation-based attacks by the policy. In other words, the action for protected senders, protected domains, or mailbox intelligence protection aren't applied to these trusted senders or sender domains. The maximum limit for these lists is 1,024 entries.
362360

363361
> [!NOTE]
364362
> Trusted domain entries don't include subdomains of the specified domain. You need to add an entry for each subdomain.
@@ -380,22 +378,18 @@ The following advanced phishing thresholds are only available in anti-phishing p
380378

381379
The chance of false positives (good messages marked as bad) increases as you increase this setting. For information about the recommended settings, see [anti-phishing policy settings in Microsoft Defender for Office 365](recommended-settings-for-eop-and-office365.md#anti-phishing-policy-settings-in-microsoft-defender-for-office-365).
382380

383-
### Spoofing vs. Impersonation
381+
### Spoofing vs. impersonation
384382

385-
**Spoofing:**
383+
Spoofing occurs when an attacker forges the sender's email address or domain to make it look like a trusted source. The attacker manipulates the sender's email address in the message header (also known as the From address, `5322.From` address, or P2 sender) to deceive the recipient.
386384

387-
- **Definition:** Spoofing occurs when an attacker forges the sender's email address or domain to make it look like a trusted source.
388-
- **Key Behavior:** The attacker manipulates the email header (e.g., "From" address) to deceive the recipient.
389-
- **Protection in EOP/Defender for Office 365:**
390-
- **EOP:** Basic spoof detection via SPF, DKIM, and DMARC validation.
391-
- **Defender for Defender for Office 365:** Enhanced spoof intelligence for better detection and mitigation of sophisticated spoofing attacks.
385+
- EOP includes basic spoofing detection via SPF, DKIM, and DMARC validation.
386+
- Defender for Office 365 includes enhanced spoof intelligence for better detection and mitigation of sophisticated spoofing attacks.
392387

393-
**Impersonation:**
388+
Impersonation occurs when an attacker mimics a trusted user, domain, or brand to trick the recipient into believing the email is genuine. The attacker often uses subtle variations of the actual user or domain name (for example, `mithun@ćóntoso.com` instead of `[email protected]`).
394389

395-
- **Definition:** Impersonation occurs when an attacker mimics a trusted user, domain, or brand to trick the recipient into believing the email is genuine.
396-
- **Key Behavior:** The attacker often uses subtle variations of the actual user’s or domain’s name (e.g., [email protected] instead of [email protected]).
397-
- **Protection in Defender for Office 365:** Impersonation protection for users, domains, and brands is an advanced feature available with Defender for Office 365, allowing administrators to define trusted entities and thresholds for detection.
390+
- EOP doesn't include impersonation protection.
391+
- Defender for Office 365 includes impersonation protection for users, domains, and brands, allowing admins to define trusted entities and thresholds for detection.
398392

399-
In impersonation attacks, email authentication checks (SPF, DKIM, and DMARC) may pass successfully because the attacker can create a lookalike domain and publish valid DNS records. Despite passing authentication, the attacker is still impersonating a trusted domain or user by using subtle variations in the domain name or display name to deceive recipients. This highlights the importance of advanced impersonation protection, as provided by Microsoft Defender for Office 365, to detect and block such sophisticated threats.
393+
Impersonation can pass email authentication checks (SPF, DKIM, and DMARC) if the attacker created a lookalike domain and published valid DNS records. Despite passing authentication, the attacker is still impersonating a trusted domain or user to deceive recipients. This behavior highlights the importance of the advanced impersonation protection provided by Defender for Office 365.
400394

401-
To understand the order of processing for the email protection types and the priority order of policies, please refer to [Order and precedence of email protection](how-policies-and-protections-are-combined.md).
395+
To understand the order of processing for the email protection types and the priority order of policies, see [Order and precedence of email protection](how-policies-and-protections-are-combined.md).

0 commit comments

Comments
 (0)