How severe is CVE-2020-11806?

CVE-2020-11806 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2020-11806 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (39th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-11806?

CVE-2020-11806 affects Mailstore Mailstore Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-11806?

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

When was CVE-2020-11806 published?

CVE-2020-11806 was published on 2020-04-23 and last updated on 2026-06-17.

CVE-2020-11806

CVE-2020-11806 is a medium-severity vulnerability in Mailstore Mailstore Server with a CVSS 3.x base score of 5.9. 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: Medium (CVSS 3.x base score 5.9)
CVSS v2: 4.3
EPSS exploit prediction: 0% (39th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-295
Affected product: Mailstore Mailstore Server
Published: 2020-04-23
Last modified: 2026-06-17

Description

In MailStore Outlook Add-in (and Email Archive Outlook Add-in) through 12.1.2, the login process does not validate the validity of the certificate presented by the server.

Frequently asked questions

What is CVE-2020-11806?: In MailStore Outlook Add-in (and Email Archive Outlook Add-in) through 12.1.2, the login process does not validate the validity of the certificate presented by the server.
How severe is CVE-2020-11806?: CVE-2020-11806 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2020-11806 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (39th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-11806?: CVE-2020-11806 affects Mailstore Mailstore Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-11806?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-11806 published?: CVE-2020-11806 was published on 2020-04-23 and last updated on 2026-06-17.

References

https://help.mailstore.com/security/MAILSTORE-SA-2020-01.txt

Affected products (1)

cpe:2.3:a:mailstore:mailstore_server:*:*:*:*:*:*:*:*

More vulnerabilities in Mailstore Mailstore Server

CVE-2019-10229 — High (CVSS 8.8): An issue was discovered in MailStore Server (and Service Provider Edition) 9.x through 11.x before 11.2.2. When the…

All CVEs affecting Mailstore Mailstore Server →

Other CWE-295 (Improper Certificate Validation) vulnerabilities

CVE-2026-4370 — Critical (CVSS 10.0): A vulnerability was identified in Juju from version 3.2.0 until 3.6.19 and from version 4.0 until 4.0.4, where the…
CVE-2026-30836 — Critical (CVSS 10.0): Step CA is an online certificate authority for secure, automated certificate management for DevOps. Versions 0.30.0-rc6…
CVE-2025-68121 — Critical (CVSS 10.0): During session resumption in crypto/tls, if the underlying Config has its ClientCAs or RootCAs fields mutated between…
CVE-2022-20703 — Critical (CVSS 10.0): Multiple vulnerabilities in Cisco Small Business RV160, RV260, RV340, and RV345 Series Routers could allow an attacker…
CVE-2021-1471 — Critical (CVSS 9.9): Multiple vulnerabilities in Cisco Jabber for Windows, Cisco Jabber for MacOS, and Cisco Jabber for mobile platforms…
CVE-2026-20184 — Critical (CVSS 9.8): A vulnerability in the integration of single sign-on (SSO) with Control Hub in Cisco Webex Services could have allowed…

Browse all CWE-295 (Improper Certificate Validation) vulnerabilities →