How severe is CVE-2020-12618?

CVE-2020-12618 has a CVSS 3.x base score of 4.8, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2020-12618 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (27th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-12618?

CVE-2020-12618 affects Emclient Em Client. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-12618?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2020-12618 published?

CVE-2020-12618 was published on 2020-08-20 and last updated on 2026-06-17.

CVE-2020-12618

CVE-2020-12618 is a medium-severity vulnerability in Emclient Em Client with a CVSS 3.x base score of 4.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: Medium (CVSS 3.x base score 4.8)
CVSS v2: 5.8
EPSS exploit prediction: 0% (27th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Emclient Em Client
Published: 2020-08-20
Last modified: 2026-06-17

Description

eM Client before 7.2.33412.0 automatically imported S/MIME certificates and thereby silently replaced existing ones. This allowed a man-in-the-middle attacker to obtain an email-validated S/MIME certificate from a trusted CA and replace the public key of the entity to be impersonated. This enabled the attacker to decipher further communication. The entire attack could be accomplished by sending a single email.

Frequently asked questions

What is CVE-2020-12618?: eM Client before 7.2.33412.0 automatically imported S/MIME certificates and thereby silently replaced existing ones. This allowed a man-in-the-middle attacker to obtain an email-validated S/MIME certificate from a trusted CA and replace the public key of the entity to be impersonated. This enabled the attacker to decipher further communication. The entire attack could be accomplished by sending a single email.
How severe is CVE-2020-12618?: CVE-2020-12618 has a CVSS 3.x base score of 4.8, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2020-12618 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (27th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-12618?: CVE-2020-12618 affects Emclient Em Client. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-12618?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-12618 published?: CVE-2020-12618 was published on 2020-08-20 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:emclient:em_client:*:*:*:*:*:*:*:*