CVE-2021-32066

Published: 15 July 2021

An issue was discovered in Ruby through 2.6.7, 2.7.x through 2.7.3, and 3.x through 3.0.1. Net::IMAP does not raise an exception when StartTLS fails with an 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."

Priority

Medium

CVSS 3 base score: 7.4

Status

References

• https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-32066
• https://www.ruby-lang.org/en/news/2021/07/07/starttls-stripping-in-net-imap/
• https://github.com/ruby/ruby/commit/a21a3b7d23704a01d34bd79d09dc37897e00922a (2.7)
• https://ubuntu.com/security/notices/USN-5020-1
• NVD
• Launchpad
• Debian

Bugs