CVE-2026-42246 — net-imap vulnerable to STARTTLS stripping via invalid response timing
Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. Prior to versions 0.3.10, 0.4.24, 0.5.14, and 0.6.4, a man-in-the-middle attacker can …
Published: 2026-05-09 · CVSS: 7.6 · CVSS 4.0
Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. Prior to versions 0.3.10, 0.4.24, 0.5.14, and 0.6.4, a man-in-the-middle attacker can cause Net::IMAP#starttls to return "successfully", without starting TLS. This issue has been patched in versions 0.3.10, 0.4.24, 0.5.14, and 0.6.4.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7