How to disable various headers: Difference between revisions
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==Resolution== | ==Resolution== | ||
1. To start with, we will first create a custom header check file, that will contain our headers that we | 1. To start with, we will first create a custom header check file, that will contain our headers that we want to ignore: | ||
$ touch /opt/zimbra/conf/custom_header_checks | $ touch /opt/zimbra/conf/custom_header_checks | ||
Line 18: | Line 18: | ||
$ zmprov mcf zimbraMtaHeaderChecks 'pcre:/opt/zimbra/conf/postfix_header_checks pcre:/opt/zimbra/conf/custom_header_checks' | $ zmprov mcf zimbraMtaHeaderChecks 'pcre:/opt/zimbra/conf/postfix_header_checks pcre:/opt/zimbra/conf/custom_header_checks' | ||
$ zmprov mcf zimbraMtaBlockedExtensionWarnRecipient FALSE | |||
Confirm the new header check file is picked up by zimbra: | |||
$ postconf | grep header_checks | |||
3. The next step would be to populate the file with data. Below is an example of this file | 3. The next step would be to populate the file with data. Below is an example of this file with various headers: | ||
/X-Virus-Scanned/ IGNORE | /X-Virus-Scanned/ IGNORE | ||
Line 39: | Line 43: | ||
The above headers are just an example. You can use any of these headers to hide sensitive information based on your needs. But beware that some MX servers will automatically mark such emails passing through as spam. Furthermore, removing all the above information will make troubleshooting very difficult. Choose which headers you would like to remove, and perform tests before implementing that on a production system. | The above headers are just an example. You can use any of these headers to hide sensitive information based on your needs. But beware that some MX servers will automatically mark such emails passing through as spam. Furthermore, removing all the above information will make troubleshooting very difficult. Choose which headers you would like to remove, and perform tests before implementing that on a production system. | ||
4. Once you finish editing the file, restart MTA to complete the setup: | |||
$ zmmtactl restart | $ zmmtactl restart | ||
{{Article Footer|Zimbra Collaboration 8.7, 8.8.9, 8.8.12| | {{Article Footer|Zimbra Collaboration 8.7, 8.8.9, 8.8.12| 7/10/2019}} | ||
{{NeedSME|SME1|SME2|COPY EDITOR}} | {{NeedSME|SME1|SME2|COPY EDITOR}} |
Revision as of 14:19, 10 July 2019
How to disable various headers
Problem
The aim of this wiki is to show how to remove sensitive email headers that are normally generated when sending an email.
Resolution
1. To start with, we will first create a custom header check file, that will contain our headers that we want to ignore:
$ touch /opt/zimbra/conf/custom_header_checks
2. Once the file is created, we are going to add it to the zimbra configuration:
$ zmprov mcf zimbraMtaHeaderChecks 'pcre:/opt/zimbra/conf/postfix_header_checks pcre:/opt/zimbra/conf/custom_header_checks' $ zmprov mcf zimbraMtaBlockedExtensionWarnRecipient FALSE
Confirm the new header check file is picked up by zimbra:
$ postconf | grep header_checks
3. The next step would be to populate the file with data. Below is an example of this file with various headers:
/X-Virus-Scanned/ IGNORE /^Received: from 127.0.0.1/ IGNORE /^X-Originating-IP:/ IGNORE /^X-Mailer:/ IGNORE /^Mime-Version:/ IGNORE /^User-Agent:/ IGNORE /^X-Sanitizer:/ IGNORE /^X-Spam-Status:/ IGNORE /^X-Spam-Level:/ IGNORE /^Message-ID:/ IGNORE /^X-MimeOLE:/ IGNORE /^X-MSMail-Priority:/ IGNORE /^Received:/ IGNORE
The above headers are just an example. You can use any of these headers to hide sensitive information based on your needs. But beware that some MX servers will automatically mark such emails passing through as spam. Furthermore, removing all the above information will make troubleshooting very difficult. Choose which headers you would like to remove, and perform tests before implementing that on a production system.
4. Once you finish editing the file, restart MTA to complete the setup:
$ zmmtactl restart