oss-sec mailing list archives

offlineimap 8.0.3 fixes CVE-2020-37248 (STARTTLS stripping)

From: Sebastian Pipping <sebastian () pipping org>
Date: Mon, 8 Jun 2026 17:29:11 +0200

Hello oss-security,


just a quick note that offlineimap 8.0.3 fixes CVE-2020-37248
"STARTTLS stripping":

  OfflineIMAP before 8.0.3 trusts the server with their STARTTLS
  capability prior to authentication, which allows STRIPTLS/man-in-the-
  middle attacks, taking over the connection and extracting account
  credentials in cleartext.

The key fix commit is…

https://github.com/OfflineIMAP/offlineimap3/commit/46505c53ef995455d66c685f9ec3ff6ea93dbb74


…and issues…

- https://github.com/OfflineIMAP/offlineimap3/issues/222
- https://github.com/OfflineIMAP/offlineimap/issues/669

…are related. The issue was first reported in 2020, hence CVE-2020-*.

Best



Sebastian

Current thread:

offlineimap 8.0.3 fixes CVE-2020-37248 (STARTTLS stripping) Sebastian Pipping (Jun 08)