Medium severity · published Jun 8, 2026
CVE-2020-37248
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…
6.5
CVSS
0.2%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
High
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 8% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
OF
OfflineIMAP · OfflineIMAP
before 8.0.3 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-37248
CVE.org
https://www.cve.org/CVERecord?id=CVE-2020-37248
github.com
https://github.com/OfflineIMAP/offlineimap/issues/669
github.com
https://github.com/OfflineIMAP/offlineimap3/commit/46505c53ef995455d66c685f9ec3ff6ea93dbb74
github.com
https://github.com/OfflineIMAP/offlineimap3/issues/222
pypi.org
https://pypi.org/project/offlineimap/#history
www.openwall.com
http://www.openwall.com/lists/oss-security/2026/06/08/3
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