How severe is CVE-2020-13163?

CVE-2020-13163 has a CVSS 3.x base score of 7.4, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.

Is CVE-2020-13163 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-13163?

CVE-2020-13163 affects Em-imap Project Em-imap. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-13163?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2020-13163 published?

CVE-2020-13163 was published on 2020-05-19 and last updated on 2026-06-17.

CVE-2020-13163

CVE-2020-13163 is a high-severity vulnerability in Em-imap Project Em-imap with a CVSS 3.x base score of 7.4. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-295.

Key facts

Severity: High (CVSS 3.x base score 7.4)
CVSS v2: 5.8
EPSS exploit prediction: 1% (51st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-295
Affected product: Em-imap Project Em-imap
Published: 2020-05-19
Last modified: 2026-06-17

Description

em-imap 0.5 uses the library eventmachine in an insecure way that allows an attacker to perform a man-in-the-middle attack against users of the library. The hostname in a TLS server certificate is not verified.

Frequently asked questions

What is CVE-2020-13163?: em-imap 0.5 uses the library eventmachine in an insecure way that allows an attacker to perform a man-in-the-middle attack against users of the library. The hostname in a TLS server certificate is not verified.
How severe is CVE-2020-13163?: CVE-2020-13163 has a CVSS 3.x base score of 7.4, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2020-13163 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-13163?: CVE-2020-13163 affects Em-imap Project Em-imap. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-13163?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2020-13163 published?: CVE-2020-13163 was published on 2020-05-19 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:em-imap_project:em-imap:0.5:*:*:*:*:*:*:*

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