CVE-2020-15953: Debian Linux

High severity, CVSS 7.4. EPSS: 2.4% chance of exploitation in the next 30 days.

LibEtPan through 1.9.4, as used in MailCore 2 through 0.6.3 and other products, has a STARTTLS buffering issue that affects IMAP, SMTP, and POP3. When a server sends a "begin TLS" response, the client reads additional data (e.g., from a meddler-in-the-middle attacker) and evaluates it in a TLS context, aka "response injection."

Affected products

• Debian Debian Linux: version 9.0 only
• Fedoraproject Fedora: version 31 only; version 32 only
• Libetpan Project Libetpan: up to and including 1.9.4
• Libmailcore MAILCORE2: up to and including 0.6.3

Published 2020-07-27. Last modified 2026-06-17.