Email privacy enforcement

1. A system comprising:

email message parsing circuitry, tracking code suspect analyzer circuitry, reporting circuitry, and message modification circuitry, wherein:

the email message parsing circuitry is operable to:

after reception of an email message via a simple mail transfer protocol (SMTP) connection and prior to the email message being made available in a mailbox of a recipient of the email message, scan the email message to extract a tracking code suspect;

the tracking code suspect analyzer circuitry is operable to:

analyze the tracking code suspect to determine, based on one or more characteristics of the tracking code suspect, whether the tracking code suspect is tracking code; and

determine a risk level associated with the tracking code suspect based on one or more of: a sender of the email message, a domain of the sender of the email message, one or more headers of the email message, and a body of the email message;

the reporting circuitry is operable to:

after a determination that the tracking code suspect is tracking code, generate a report that indicates the presence of tracking code in the email message and indicates the determined risk level; and

the message modification circuitry is operable to replace the tracking code suspect in the email message with replacement content.

2. The system of claim 1 , wherein the one or more characteristics of the tracking code suspect comprise a transparency attribute and/or size attribute of an image associated with the tracking code suspect.

3. The system of claim 1 , wherein the one or more characteristics of the tracking code suspect comprise a uniform resource locator (URL) of the tracking code suspect.

4. The system of claim 1 , wherein the one or more characteristics of the tracking code suspect comprise a particular domain or subdomain in a uniform resource locator (URL) of the tracking code suspect.

5. The system of claim 1 , wherein the one or more characteristics of the tracking code suspect comprise a particular query string in a uniform resource locator (URL) of the tracking code suspect.

6. The system of claim 1 , wherein the one or more characteristics of the tracking code suspect comprise a particular path element or combination of path elements in a uniform resource locator (URL) of the tracking code suspect.

7. The system of claim 1 , wherein the one or more characteristics of the tracking code suspect comprise a domain or Internet Protocol (IP) address corresponding to a uniform resource locator (URL) of the tracking code suspect.

8. The system of claim 1 , wherein the one or more characteristics of the tracking code suspect comprise a length, in number of alphanumeric characters, of the tracking code suspect.

9. The system of claim 1 , wherein the one or more characteristics of the tracking code suspect comprise characteristics of visible content of an image associated with the tracking code suspect.

10. The system of claim 9 , wherein the characteristics of visible content of the image comprises color variation among pixels of the image.

11. The system of claim 1 , wherein the one or more characteristics of the tracking code suspect comprise presence of a particular substring in a uniform resource locator (URL) of the tracking code suspect.

12. The system of claim 1 , wherein the one or more characteristics of the tracking code suspect comprise a uniform resource locator (URL) of the tracking code suspect matching a particular regular expression.

13. The system of claim 1 , wherein the tracking code suspect comprises a first uniform resource locator (URL).

14. The system of claim 13 , wherein the replacement content comprises a second URL.

15. The system of claim 14 , wherein the second URL comprises the first URL as a query string.

16. The system of claim 14 , wherein the second URL comprises the first URL as one or more path elements.

17. The system of claim 14 , comprising content cache interface circuitry operable to send the second URL to content caching circuitry.

18. The system of claim 17 , comprising the content caching circuitry and wherein the content caching circuitry is operable to fetch content from the first URL and store the content at a location pointed to by the second URL.

19. The system of claim 1 , wherein:

the tracking code suspect analyzer circuitry is operable to:

determine which one of a plurality of categories to assign to identified tracking code based on a domain or IP address associated with the identified tracking code; and

assign the one of the plurality of categories to the identified tracking code.