How does ProofPoint affect email authentication for organizational Outlook domains?

Summary

Proofpoint, as an intermediary email security solution, can significantly affect email authentication for organizational Outlook domains. It alters the email path, potentially leading to SPF, DKIM, and DMARC validation failures because the receiving server sees Proofpoint's IP address instead of the original sender's. To mitigate these issues, organizations should configure Exchange Online Connectors to recognize Proofpoint's IPs as trusted sources, implement ARC (Authenticated Received Chain) to preserve authentication results across multiple hops, and enable Enhanced Filtering for Connectors. Regular monitoring of email logs and careful analysis of email headers are also essential. Additionally, proper management of bypass lists, correct configuration of internal domains, and the use of TLS encryption contribute to a more secure and reliable email system. Verifying DMARC settings is also a crucial step to maintain email authentication integrity.

Key findings

  • SPF/DKIM Failures: Proofpoint can cause SPF and DKIM failures as its IP address may not match the sender's records.
  • Header Alteration: Proofpoint's filtering can flag legitimate emails or alter headers, triggering spam filters.
  • IP Address Discrepancy: EOP sees Proofpoint's IP instead of the original sender's, affecting authentication checks.
  • Authentication Result Stripping: Proofpoint might strip or alter headers essential for SPF, DKIM, and DMARC validation.
  • ARC Importance: ARC is critical for preserving authentication results across multiple email hops.

Key considerations

  • Connector Configuration: Properly configure Exchange Online Connectors for Proofpoint.
  • SPF Record Updates: Ensure SPF records include Proofpoint's IPs or use ARC.
  • Header Analysis: Analyze email headers to understand Proofpoint's impact.
  • Log Monitoring: Regularly monitor email logs for authentication failures and misconfigurations.
  • Bypass List Management: Carefully manage bypass lists to prevent security vulnerabilities.
  • Internal Domain Setup: Configure internal domains correctly for proper authentication.
  • TLS Encryption: Use TLS encryption to secure email communications.
  • DMARC Verification: Regularly verify DMARC settings

What email marketers say
10Marketer opinions

Proofpoint, as a third-party email security solution, impacts email authentication for organizational Outlook domains by altering email paths and potentially causing SPF, DKIM, and DMARC validation failures. This is because Proofpoint's IP addresses may not match the sender's SPF records. Mitigation strategies include configuring Exchange Online Connectors to recognize Proofpoint's IPs, implementing ARC to preserve authentication results, carefully analyzing email headers, monitoring email logs, managing bypass lists judiciously, configuring internal domains correctly, and using TLS encryption. Proper configuration and monitoring are crucial to maintaining email deliverability and security.

Key opinions

  • SPF Failures: Proofpoint can cause SPF failures because its IP addresses may not match the sender's SPF records.
  • Header Alteration: Proofpoint's filtering might flag legitimate emails or alter headers, triggering spam filters.
  • Authentication Results: It's crucial to ensure Proofpoint is configured to properly forward authentication results to Exchange Online.
  • Inbound Connectors: Configuring Exchange Online Connectors to recognize Proofpoint's IPs as trusted sources is essential.
  • Email Log Insights: Email logs provide insights into authentication failures, spam filtering, and potential misconfigurations.

Key considerations

  • SPF Records: Organizations should ensure their SPF records include Proofpoint's IPs or use mechanisms like ARC.
  • ARC Implementation: Implementing ARC helps preserve authentication results across multiple hops.
  • Header Analysis: Carefully analyze email headers to understand the email's path and modifications made by Proofpoint.
  • Log Monitoring: Regularly monitor email logs to identify and address authentication issues proactively.
  • Bypass List Management: Manage bypass lists carefully to avoid introducing security vulnerabilities.
  • Internal Domain Configuration: Correctly configure internal domains to ensure internal emails are properly authenticated.
  • TLS Encryption: Use TLS encryption to secure email communications and protect data integrity.
Marketer view

Email marketer from Security Forums emphasizes the importance of regularly monitoring email logs when using Proofpoint. They explain that logs can provide valuable insights into email authentication failures, spam filtering issues, and potential misconfigurations. Proactive monitoring allows organizations to quickly identify and address any problems that may arise.

January 2023 - Security Forums
Marketer view

Email marketer from Super User suggests carefully analyzing email headers when using Proofpoint. They recommend examining the `Received:` headers to understand the email's path and identify any modifications made by Proofpoint. This analysis can help pinpoint issues with SPF, DKIM, or DMARC validation and ensure proper configuration.

November 2022 - Super User
Marketer view

Email marketer from Cloud Security Blog advises that organizations should use TLS encryption with Proofpoint to secure email communications. TLS encryption protects email content during transit, preventing eavesdropping and ensuring data integrity. Proper TLS configuration enhances the overall security posture of the email system.

May 2024 - Cloud Security Blog
Marketer view

Email marketer from Spiceworks Community shares that to handle email authentication when using Proofpoint with Exchange Online, it's crucial to ensure that Proofpoint is configured to properly forward authentication results. They suggest verifying that Proofpoint is not stripping or altering headers that are essential for SPF, DKIM, and DMARC validation. Additionally, they recommend using ARC (Authenticated Received Chain) to preserve authentication results across multiple hops.

March 2022 - Spiceworks Community
Marketer view

Email marketer from Stack Overflow shares that when using Proofpoint or other third-party email security solutions, SPF records can be affected. The receiving server checks the SPF record of the sending domain, and if the email is routed through Proofpoint, the IP address making the final delivery might not match the IPs listed in the sender's SPF record, leading to SPF failures. Organizations should ensure their SPF records include Proofpoint's IPs or use mechanisms like ARC to validate email authenticity.

June 2023 - Stack Overflow
Marketer view

Marketer from Email Geeks explains that if Proofpoint is being used, authentication failures are expected. If the email is incoming, the inbound connector on 365 will exclude those authentication failures from spam.

September 2022 - Email Geeks
Marketer view

Email marketer from IT Forums recommends that organizations configure their internal domains correctly when using Proofpoint. This includes setting up internal relay domains to ensure that emails sent within the organization are properly authenticated and delivered. Without proper configuration, internal emails may be flagged as spam or experience delivery issues.

August 2021 - IT Forums
Marketer view

Email marketer from Reddit discusses how Proofpoint can sometimes cause deliverability issues if not configured correctly. They mention that Proofpoint's filtering might flag legitimate emails or alter headers in a way that triggers spam filters on the receiving end. Regular monitoring of email logs and Proofpoint configurations is recommended to mitigate these issues.

October 2022 - Reddit
Marketer view

Email marketer from Email Security Forum discusses using bypass lists in Proofpoint to allow certain senders to skip some security checks. While this can help with legitimate emails being incorrectly flagged, it's crucial to carefully manage these lists to avoid introducing security vulnerabilities.

April 2021 - Email Security Forum
Marketer view

Email marketer from TechNet Forums recommends configuring Exchange Online Connectors specifically for Proofpoint. This involves creating inbound connectors that recognize Proofpoint's IP addresses and treat them as trusted sources. By doing so, Exchange Online can accurately assess the email's authentication status based on the original sender, rather than Proofpoint's servers.

April 2023 - TechNet Forums

What the experts say
1Expert opinion

ProofPoint's filtering process can disrupt SPF and DKIM records, as the IP address making the final delivery might not align with the sender's SPF record. It is crucial to verify DMARC settings to maintain email authentication integrity.

Key opinions

  • SPF/DKIM Impact: ProofPoint filtering can affect SPF and DKIM records.
  • IP Mismatch: The final delivery IP may not match the sender's SPF record.

Key considerations

  • DMARC Verification: Check DMARC settings to ensure email authentication.
Expert view

Expert from Word to the Wise explains that when ProofPoint filters email it can affect SPF and DKIM records. A receiving server checks the SPF record of the sending domain, and if the email is routed through Proofpoint, the IP address making the final delivery might not match the IPs listed in the sender's SPF record. She suggests that it is best practice to also check DMARC settings if this happens.

May 2023 - Word to the Wise

What the documentation says
6Technical articles

Proofpoint, acting as an intermediary for inbound email, can impact email authentication in organizational Outlook domains. EOP sees Proofpoint's IP instead of the original sender's, potentially affecting spam filtering. Proper configuration of connectors, especially Enhanced Filtering, helps Exchange Online identify the original sender. ARC (Authenticated Received Chain) preserves authentication results through multiple hops, mitigating authentication failures. Configuring inbound connectors to recognize Proofpoint's IPs is crucial to avoid SPF/DKIM failures.

Key findings

  • EOP IP Address: EOP may see Proofpoint's IP instead of the original sender's, affecting spam filtering.
  • Authentication Impact: Proofpoint's intermediary role can impact SPF, DKIM, and DMARC validation.
  • ARC Preservation: ARC preserves authentication results when email is processed by intermediaries like Proofpoint.

Key considerations

  • Connector Configuration: Configure connectors correctly to ensure accurate sender identification.
  • Enhanced Filtering: Implement Enhanced Filtering for Connectors in Exchange Online.
  • ARC Implementation: Implement ARC to mitigate authentication failures caused by third-party security solutions.
  • Inbound Connectors: Configure inbound connectors to recognize Proofpoint's IPs as trusted.
Technical article

Documentation from Proofpoint Support explains configuring inbound connectors to ensure mail flow and authentication is handled correctly. It mentions the importance of setting up connectors that recognize Proofpoint's IPs as trusted to avoid SPF or DKIM failures on legitimate emails.

January 2024 - Proofpoint Support
Technical article

Documentation from RFC Editor details the technical specifications of ARC (Authenticated Received Chain). It explains how ARC works to preserve email authentication results by creating a chain of signatures that validate the authenticity of each hop in the email's journey. This ensures that receiving servers can trust the email's authentication status, even after it has been processed by intermediaries like Proofpoint.

December 2022 - RFC Editor
Technical article

Documentation from Microsoft Learn explains that Exchange Online Protection (EOP) examines inbound email headers and content. When Proofpoint or similar services are in front of Office 365, EOP might see the authenticating IP address of Proofpoint rather than the original sender, potentially affecting the effectiveness of EOP's spam filtering and authentication checks. It's important to configure connectors correctly to ensure accurate sender identification.

August 2022 - Microsoft Learn
Technical article

Documentation from DMARC.org explains that ARC (Authenticated Received Chain) provides a way to preserve email authentication results when an email is forwarded or processed by intermediaries like Proofpoint. ARC allows the receiving server to trust the authentication status of the email, even if it has passed through multiple hops. Implementing ARC can help mitigate authentication failures caused by third-party email security solutions.

October 2023 - DMARC.org
Technical article

Documentation from Proofpoint Support details that Proofpoint acts as an intermediary for inbound email. It scans emails for threats before relaying them to the organization's email server (e.g., Exchange Online). This process can alter the email's path and IP addresses, which can impact SPF, DKIM, and DMARC validation. Admins should configure Proofpoint to properly handle authentication results and ensure they are passed to the receiving server.

May 2024 - Proofpoint Support
Technical article

Documentation from Microsoft Learn states that when using a third-party service like Proofpoint, it's important to configure Enhanced Filtering for Connectors in Exchange Online. This feature helps Exchange Online accurately identify the original sender of the email, even when it's relayed through Proofpoint. Proper configuration ensures that SPF, DKIM, and DMARC checks are performed against the original sender's domain, improving email authentication accuracy.

October 2023 - Microsoft Learn