Where did you install Firefox from? Help Mozilla uncover 3rd party websites that offer problematic Firefox installation by taking part in our campaign. There will be swag, and you'll be featured in our blog if you manage to report at least 10 valid reports!

This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Avatar for Username

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

This thread was archived. Please ask a new question if you need help.

Hi Team, This is for your information that we can alter sender email ID from thunderbird while sending out email to others and whichcanbeusedforemail spoofing

  • 1 reply
  • 1 has this problem
  • 5 views
  • Last reply by Matt

amathakur
amathakur
more options

Hi Team,

This is for your information that we can alter sender email ID from thunderbird version 45 or above while sending out email to others and which can be used for email spoofing.

Like i have configured my email id [abc@test.com] in thunderbird but while composing email I can easily edit the sender's/from email id [abc@test.com] to anything hyg@hello.com etc, which email id/domain is even not available or available.

By using this I can send the emails to any one.This can be used for email spoofing.

Please solve this bug.

Thanks, Amar

Hi Team, This is for your information that we can alter sender email ID from thunderbird version 45 or above while sending out email to others and which can be used for email spoofing. Like i have configured my email id [abc@test.com] in thunderbird but while composing email I can easily edit the sender's/from email id [abc@test.com] to anything hyg@hello.com etc, which email id/domain is even not available or available. By using this I can send the emails to any one.This can be used for email spoofing. Please solve this bug. Thanks, Amar

All Replies (1)

Matt
Matt
  • Moderator
  • Top 10 Contributor
more options

This is not a bug, it is feature introduced in version 45. It is not new.

See https://support.mozilla.org/en-US/kb/new-thunderbird-45 And the bug it arose from https://bugzilla.mozilla.org/show_bug.cgi?id=87987

Note that a well configured SMTP server will not allow mail to be sent from accounts the user does not have access to. But having the ability to change the sender yo the boss you are writing on behalf of is handy.