CVE-2026-42223

MEDIUM
Published May 4, 2026 Modified May 6, 2026 CWE-200

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.

CVSS v3.1 Score

6.5
MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

EPSS — Exploit Prediction

0.0004
Probability of exploitation
0.11%
Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-200 CWE-200

Affected Products

Vendor Product
nginxui nginx_ui

References

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. It has a CVSS v3.1 base score of 6.5 (MEDIUM).
How severe is CVE-2026-42223? +
CVE-2026-42223 has a CVSS v3.1 score of 6.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance. The EPSS score is 0.0004, placing it in the 0th percentile for exploitation probability.
What products are affected by CVE-2026-42223? +
CVE-2026-42223 affects products from nginxui, specifically: nginx_ui. Check the affected products table above for specific version ranges.
How do I check if I'm vulnerable to CVE-2026-42223? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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