Posted by shugo on 7 Jul 2021
A StartTLS stripping vulnerability was discovered in Net::IMAP. This vulnerability has been assigned the CVE identifier CVE-2021-32066. We strongly recommend upgrading Ruby.
net-imap is a default gem in Ruby 3.0.1 but it has a packaging issue, so please upgrade Ruby itself.
Net::IMAP does not raise an exception when StartTLS fails with an unknown response, which might allow man-in-the-middle attackers to bypass the TLS protections by leveraging a network position between the client and the registry to block the StartTLS command, aka a “StartTLS stripping attack.”
- Ruby 2.6 series: 2.6.7 and earlier
- Ruby 2.7 series: 2.7.3 and earlier
- Ruby 3.0 series: 3.0.1 and earlier
Thanks to Alexandr Savca for reporting the issue.
- Originally published at 2021-07-07 09:00:00 UTC