public:emai:malware

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public:emai:malware [2023-03-09 09:41] veselypublic:emai:malware [2023-03-09 09:42] – [Monitoring and filtering agenda] vesely
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   * [[:public:emai:malware#spf_hard_fail|SPF hard fail]] - sending server __is not on the allowed list__  provided by domain's owner and the domain owner asks for message blocking.   * [[:public:emai:malware#spf_hard_fail|SPF hard fail]] - sending server __is not on the allowed list__  provided by domain's owner and the domain owner asks for message blocking.
-  * [[:public:emai:malware#spf_soft_fail|SPF soft fail]] - +  * [[:public:emai:malware#spf_soft_fail|SPF soft fail]] - <font inherit/inherit;;#f39c12;;inherit>[Suspicious - SPF - soft fail]</font>  - sending server is not listed among allowed ones, but the domain owner allow message passing with warning. 
- <font inherit/inherit;;#f39c12;;inherit>[Suspicious - SPF - soft fail]</font>  - sending server is not listed among allowed ones, but the domain owner allow message passing with warning. +  * [[:public:emai:malware#spf_bad_alignment|SPF bad alignment]] - <font inherit/inherit;;#f39c12;;inherit>[Covert sender]</font>  - verify the authenticity of the domain sending the email by using two diffrenent header signatures in the message. 
-  * [[:public:emai:malware#spf_bad_alignment|SPF bad alignment]] - +  * [[:public:emai:malware#bad_dmarc|Bad DMARC]] - <font inherit/inherit;;#f39c12;;inherit>[Bad DMARC]</font>  - the sender's domain does not have DMARC record and SPF set properly. 
- <font inherit/inherit;;#f39c12;;inherit>[Covert sender]</font>  - verify the authenticity of the domain sending the email by using two diffrenent header signatures in the message. +  * [[:public:emai:malware#bad_dmarc|Bad ARC]] - <font inherit/inherit;;#f39c12;;inherit>[Suspicious - bad ARC]</font>  - the sender's email has ARC Seal but it's validation did not succed (e.g. invalid calculated email hash).
-  * [[:public:emai:malware#bad_dmarc|Bad DMARC]] - +
- <font inherit/inherit;;#f39c12;;inherit>[Bad DMARC]</font>  - the sender's domain does not have DMARC record and SPF set properly. +
-  * [[:public:emai:malware#bad_dmarc|Bad ARC]] - +
- <font inherit/inherit;;#f39c12;;inherit>[Suspicious - bad ARC]</font>  - the sender's email has ARC Seal but it's validation did not succed (e.g. invalid calculated email hash).+
   * [[:public:emai:malware#ip_reputation_database_-_dnsbl|DNSBL listed]] -   * [[:public:emai:malware#ip_reputation_database_-_dnsbl|DNSBL listed]] -
  <font inherit/inherit;;#f39c12;;inherit>[IP reputation - DNSBL listed]</font>  - the sender's IP is listed in SPAM database.  <font inherit/inherit;;#f39c12;;inherit>[IP reputation - DNSBL listed]</font>  - the sender's IP is listed in SPAM database.
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 **Example of spoof email:** **Example of spoof email:**
  
-MAIL FROM: **johndoe2 <font inherit/inherit;;#2980b9;;inherit>@gmail.com</font> ** \\ +MAIL FROM: **johndoe2 
-From: **john.doe <font inherit/inherit;;#d35400;;inherit>@cerge-ei.cz</font> ** \\ + <font inherit/inherit;;#2980b9;;inherit>@gmail.com</font> ** \\ 
-To: **jane.dow <font inherit/inherit;;#d35400;;inherit>@cerge-ei.cz</font> **+From: **john.doe 
 + <font inherit/inherit;;#d35400;;inherit>@cerge-ei.cz</font> ** \\ 
 +To: **jane.dow 
 + <font inherit/inherit;;#d35400;;inherit>@cerge-ei.cz</font> **
  
 Such email is suspicious. Some user with an account at Gmail (johndoe2@gmail.com) set his profile to use institutional email address (john.doe@cerge-ei.cz). \\ Such email is suspicious. Some user with an account at Gmail (johndoe2@gmail.com) set his profile to use institutional email address (john.doe@cerge-ei.cz). \\
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 </code> </code>
  
-https://en.wikipedia.org/wiki/Authenticated_Received_Chain+[[https://en.wikipedia.org/wiki/Authenticated_Received_Chain|https://en.wikipedia.org/wiki/Authenticated_Received_Chain]]
  
-https://dmarc.org/presentations/ARC-Overview-2016Q3-v01.pdf+[[https://dmarc.org/presentations/ARC-Overview-2016Q3-v01.pdf|https://dmarc.org/presentations/ARC-Overview-2016Q3-v01.pdf]]
  
 ===== Reputation databases - Blacklists ===== ===== Reputation databases - Blacklists =====
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 Certain sort of newsletter senders wants to track recipients clicks (to monetize and/or monitor recipient behavior) so they conceal the target URL behind their own hash. It is then undecidable whether the redirected URL is OK or not (phishing). Certain sort of newsletter senders wants to track recipients clicks (to monetize and/or monitor recipient behavior) so they conceal the target URL behind their own hash. It is then undecidable whether the redirected URL is OK or not (phishing).
  
-**Example** +**Example** <font inherit/inherit;;#c0392b;;inherit>**Obfuscated/unresolvable link**:</font>  If you get the newsletter from **bostonglobe.com**  with links in the form [[https://bostonglobe.us11|https://bostonglobe.us11]].**list-manage.com/track/click?u=90f9e490a86&id=0c98f5&e=e8fef**  , it cannot be said what is the targeting URL. Hence the ** <font inherit/inherit;;#c0392b;;inherit>warning about uncertain content is added</font> **.
- <font inherit/inherit;;#c0392b;;inherit>**Obfuscated/unresolvable link**:</font> If you get the newsletter from **bostonglobe.com**  with links in the form [[https://bostonglobe.us11|https://bostonglobe.us11]].**list-manage.com/track/click?u=90f9e490a86&id=0c98f5&e=e8fef**  , it cannot be said what is the targeting URL. Hence the ** <font inherit/inherit;;#c0392b;;inherit>warning about uncertain content is added</font> **.+
  
 ** <font inherit/inherit;;#27ae60;;inherit>Regular/direct link</font> **: If the newsletter from **newyorker.com**  contains links in the form [[https://link|https://link]].**newyorker.com/view/5dc1b3fc91f4/03075c2d**  , it may be tracked down to the target URL and **is considered safe**. ** <font inherit/inherit;;#27ae60;;inherit>Regular/direct link</font> **: If the newsletter from **newyorker.com**  contains links in the form [[https://link|https://link]].**newyorker.com/view/5dc1b3fc91f4/03075c2d**  , it may be tracked down to the target URL and **is considered safe**.
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 //Added subject tag: [Suspicious - header analysis]// //Added subject tag: [Suspicious - header analysis]//
  
-//Added warning text: "Deepheader analysis examines header for spam characteristics. Don't click any link unless you are certain it's legitimate.////"// +//Added warning text: "Deepheader analysis examines header for spam characteristics. Don't click any link unless you are certain it's legitimate.////"// <font inherit/inherit;;#c0392b;;inherit>Tool to examine message header (displays human-readable content):</font> [[https://mha.azurewebsites.net/|https://mha.azurewebsites.net/]]
- <font inherit/inherit;;#c0392b;;inherit>Tool to examine message header (displays human-readable content):</font> [[https://mha.azurewebsites.net/|https://mha.azurewebsites.net/]]+
  
 Deepheader analysis examines the entire message header for spam characteristics. Deepheader analysis examines the entire message header for spam characteristics.
  • /var/www/html/dokuwiki/data/pages/public/emai/malware.txt
  • Last modified: 2023-03-09 12:13
  • by vesely