How severe is CVE-2020-5909?

CVE-2020-5909 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2020-5909 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (32nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-5909?

CVE-2020-5909 primarily affects F5 Nginx Controller. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-5909?

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

When was CVE-2020-5909 published?

CVE-2020-5909 was published on 2020-07-02 and last updated on 2026-06-17.

CVE-2020-5909

CVE-2020-5909 is a medium-severity vulnerability in F5 Nginx Controller with a CVSS 3.x base score of 5.4. 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: Medium (CVSS 3.x base score 5.4)
CVSS v2: 5.8
EPSS exploit prediction: 0% (32nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-295
Affected product: F5 Nginx Controller
Published: 2020-07-02
Last modified: 2026-06-17

Description

In versions 3.0.0-3.5.0, 2.0.0-2.9.0, and 1.0.1, when users run the command displayed in NGINX Controller user interface (UI) to fetch the agent installer, the server TLS certificate is not verified.

Frequently asked questions

What is CVE-2020-5909?: In versions 3.0.0-3.5.0, 2.0.0-2.9.0, and 1.0.1, when users run the command displayed in NGINX Controller user interface (UI) to fetch the agent installer, the server TLS certificate is not verified.
How severe is CVE-2020-5909?: CVE-2020-5909 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2020-5909 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (32nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-5909?: CVE-2020-5909 primarily affects F5 Nginx Controller. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-5909?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-5909 published?: CVE-2020-5909 was published on 2020-07-02 and last updated on 2026-06-17.

References

https://support.f5.com/csp/article/K31150658

Affected products (2)

cpe:2.3:a:f5:nginx_controller:*:*:*:*:*:*:*:*
cpe:2.3:a:f5:nginx_controller:1.0.1:*:*:*:*:*:*:*

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