How severe is CVE-2026-42223?

CVE-2026-42223 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2026-42223 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (21st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-42223?

CVE-2026-42223 affects Nginxui Nginx Ui. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-42223?

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

Does CVE-2026-42223 have an EU (EUVD) identifier?

Yes. CVE-2026-42223 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-27140.

When was CVE-2026-42223 published?

CVE-2026-42223 was published on 2026-05-04 and last updated on 2026-06-17.

CVE-2026-42223

CVE-2026-42223 is a medium-severity vulnerability in Nginxui Nginx Ui 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-200.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
EPSS exploit prediction: 0% (21st percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-27140
Weakness: CWE-200
Affected product: Nginxui Nginx Ui
Published: 2026-05-04
Last modified: 2026-06-17

Description

Nginx UI is a web user interface for the Nginx web server. Prior to version 2.3.8, the GetSettings API handler (api/settings/settings.go:24-65) serializes all settings structs to JSON and returns them to authenticated users. Many sensitive fields are tagged with protected:"true" - however, this tag is only enforced during writes (via ProtectedFill in SaveSettings) and is completely ignored during reads. This exposes 40+ protected fields including JwtSecret (enabling auth token forgery), NodeSecret (enabling cluster node impersonation), OIDC ClientSecret (enabling OAuth account takeover), and the IP whitelist configuration. This issue has been patched in version 2.3.8.

Frequently asked questions

What is CVE-2026-42223?: Nginx UI is a web user interface for the Nginx web server. Prior to version 2.3.8, the GetSettings API handler (api/settings/settings.go:24-65) serializes all settings structs to JSON and returns them to authenticated users. Many sensitive fields are tagged with protected:"true" - however, this tag is only enforced during writes (via ProtectedFill in SaveSettings) and is completely ignored during reads. This exposes 40+ protected fields including JwtSecret (enabling auth token forgery), NodeSecret (enabling cluster node impersonation), OIDC ClientSecret (enabling OAuth account takeover), and the IP whitelist configuration. This issue has been patched in version 2.3.8.
How severe is CVE-2026-42223?: CVE-2026-42223 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2026-42223 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (21st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-42223?: CVE-2026-42223 affects Nginxui Nginx Ui. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-42223?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-42223 have an EU (EUVD) identifier?: Yes. CVE-2026-42223 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-27140.
When was CVE-2026-42223 published?: CVE-2026-42223 was published on 2026-05-04 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:nginxui:nginx_ui:*:*:*:*:*:*:*:*

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