0xJacky nginx-ui up to 2.3.7 missing authentication

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.7$0-$5k0.00

Summaryinfo

A vulnerability described as critical has been identified in 0xJacky nginx-ui up to 2.3.7. This issue affects some unknown processing. The manipulation results in missing authentication. This vulnerability is reported as CVE-2026-42221. The attack can be launched remotely. No exploit exists. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability, which was classified as critical, was found in 0xJacky nginx-ui up to 2.3.7. Affected is an unknown code block. The manipulation with an unknown input leads to a missing authentication vulnerability. CWE is classifying the issue as CWE-306. The product does not perform any authentication for functionality that requires a provable user identity or consumes a significant amount of resources. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

Nginx UI is a web user interface for the Nginx web server. From version 2.0.0 to before version 2.3.8, an unauthenticated network attacker can claim the initial administrator account on a fresh nginx-ui instance during the first-run setup window. The public /api/install endpoint is reachable without authentication, and the request-encryption flow only protects payload confidentiality in transit; it does not authenticate who is allowed to perform installation. A remote attacker who reaches the service before the legitimate operator can set the admin email, username, and password, causing permanent initial-instance takeover. This issue has been patched in version 2.3.8.

The advisory is available at github.com. This vulnerability is traded as CVE-2026-42221 since 04/25/2026. The exploitability is told to be difficult. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. The technical details are unknown and an exploit is not available.

Upgrading to version 2.3.8 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-27135). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

Vendor

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.8
VulDB Meta Temp Score: 6.7

VulDB Base Score: 5.6
VulDB Temp Score: 5.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 8.1
CNA Vector (GitHub_M): 🔒

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Missing authentication
CWE: CWE-306 / CWE-287
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: nginx-ui 2.3.8

Timelineinfo

04/25/2026 CVE reserved
05/04/2026 +9 days Advisory disclosed
05/04/2026 +0 days VulDB entry created
05/05/2026 +1 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-42221 (🔒)
GCVE (CVE): GCVE-0-2026-42221
GCVE (VulDB): GCVE-100-361002
EUVD: 🔒

Entryinfo

Created: 05/04/2026 22:46
Updated: 05/05/2026 02:43
Changes: 05/04/2026 22:46 (64), 05/05/2026 02:43 (1)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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