How severe is CVE-2020-14455?

CVE-2020-14455 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2020-14455 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (65th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-14455?

CVE-2020-14455 affects Mattermost Mattermost Desktop. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-14455?

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

When was CVE-2020-14455 published?

CVE-2020-14455 was published on 2020-06-19 and last updated on 2026-06-17.

CVE-2020-14455

CVE-2020-14455 is a medium-severity vulnerability in Mattermost Mattermost Desktop with a CVSS 3.x base score of 6.5. 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-287.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 4.3
EPSS exploit prediction: 1% (65th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Mattermost Mattermost Desktop
Published: 2020-06-19
Last modified: 2026-06-17

Description

An issue was discovered in Mattermost Desktop App before 4.4.0. Prompting for HTTP Basic Authentication is mishandled, allowing phishing, aka MMSA-2020-0007.

Frequently asked questions

What is CVE-2020-14455?: An issue was discovered in Mattermost Desktop App before 4.4.0. Prompting for HTTP Basic Authentication is mishandled, allowing phishing, aka MMSA-2020-0007.
How severe is CVE-2020-14455?: CVE-2020-14455 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2020-14455 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (65th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-14455?: CVE-2020-14455 affects Mattermost Mattermost Desktop. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-14455?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-14455 published?: CVE-2020-14455 was published on 2020-06-19 and last updated on 2026-06-17.

References

https://mattermost.com/security-updates/

Affected products (1)

cpe:2.3:a:mattermost:mattermost_desktop:*:*:*:*:*:*:*:*

More vulnerabilities in Mattermost Mattermost Desktop

CVE-2016-11064 — Critical (CVSS 9.8): An issue was discovered in Mattermost Desktop App before 3.4.0. Strings could be executed as code via injection.
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Other CWE-287 (Improper Authentication) vulnerabilities

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CVE-2026-59500 — Critical (CVSS 10.0): CWE-287: Improper Authentication
CVE-2024-27253 — Critical (CVSS 10.0): IBM DOORS Next 7.0.3 through 7.0.3 Interim Fix 018 could allow an authenticated user to bypass security logic to…
CVE-2026-56162 — Critical (CVSS 10.0): Improper authentication in Azure SQL Database allows an unauthorized attacker to elevate privileges over a network.
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Browse all CWE-287 (Improper Authentication) vulnerabilities →