CVE-2020-37248

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.

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CVSS v3.1 Score

6.5

MEDIUM

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N

EPSS — Exploit Prediction

0.0019

Probability of exploitation

0.08%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-348 CWE-348

References

Other References

https://github.com/OfflineIMAP/offlineimap/issues/669 https://github.com/OfflineIMAP/offlineimap3/commit/46505c53ef995455d66c685f9ec3ff6ea93dbb74 https://github.com/OfflineIMAP/offlineimap3/issues/222 https://pypi.org/project/offlineimap/#history http://www.openwall.com/lists/oss-security/2026/06/08/3

Frequently Asked Questions

What is 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 extracting account credentials in cleartext. It has a CVSS v3.1 base score of 6.5 (MEDIUM).

How severe is CVE-2020-37248? +

CVE-2020-37248 has a CVSS v3.1 score of 6.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance. The EPSS score is 0.0019, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2020-37248? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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