CVE-2026-33031: Nginx-UI Disabled Users Retain Full API Vulnerability

HIGH
Advisory Identifier: GHSA-x234-x5vq-cc2v
CVSS 8.1
CWE-284 CWE-863
Published
Advisory Summary

CVE-2026-33031 is a HIGH (CVSS 8.1) disabled users retain full api vulnerability (CWE-284: Improper Access Control) affecting Nginx-UI libraries in the Go ecosystem. The issue involves disabled users retain full api access through previously issued bearer tokens. Remediation is available by upgrading affected packages to version 1.9.10-0.20260314152518-7b66578adb47.

CVE-2026-33031 at a Glance

CVE Identifier CVE-2026-33031
GHSA Identifier GHSA-x234-x5vq-cc2v
Severity HIGH
CVSS v3.1 Base Score 8.1
CWE Classification CWE-284: Improper Access Control
Affected Product Nginx-UI
Package Ecosystem Go
Published Date
Last Updated

Security Impact

CVSS: 8.1

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required Low (PR:L)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality High (C:H)
Integrity High (I:H)
Availability None (A:N)

How to Fix CVE-2026-33031

To remediate this vulnerability, upgrade all affected Nginx-UI dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

github.com/0xJacky/Nginx-UI fixed: 1.9.10-0.20260314152518-7b66578adb47
Upgrade github.com/0xJacky/Nginx-UI to 1.9.10-0.20260314152518-7b66578adb47
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release:

inspect dependencies for github.com/0xJacky/Nginx-UI

How to Check if You Are Affected

To determine whether your application is affected by CVE-2026-33031, inspect your project dependencies for Nginx-UI:

inspect dependencies for github.com/0xJacky/Nginx-UI

Analyze the terminal output to locate any version of Nginx-UI in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 1.9.10-0.20260314152518-7b66578adb47), your application is affected.

Note: Verify declared build manifests and deployed runtime container environments.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-284: Improper Access Control, where the product does not restrict or incorrectly restricts access to a resource from an unauthorized actor. In Nginx-UI, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

### Summary A user who was disabled by an administrator can use previously issued API tokens for up to the token lifetime. In practice, disabling a compromised account does not actually terminate that user’s access, so an attacker who already stole a JWT can continue reading and modifying protected resources after the account is marked disabled. Since tokens can be used to create new accounts, it is possible the disabled user to maintain the privilege. ### Details The application exposes an account-level disable control through the users management API. Login process correctly enforces that control: https://github.com/0xJacky/nginx-ui/blob/6ec542fd97abf2c5950f374f78a32938ad0030e6/internal/user/login.go#L29-L31 However, token-based authentication does not enforce the same check (This code validates token structure and expiry, but returns that user object without checking `user.Status`.): https://github.com/0xJacky/nginx-ui/blob/6ec542fd97abf2c5950f374f78a32938ad0030e6/internal/user/user.go#L44-L139 There’s also no token revocation feature, unlike when a password is changed: https://github.com/0xJacky/nginx-ui/blob/6ec542fd97abf2c5950f374f78a32938ad0030e6/api/user/user.go#L38-L51 As a result, a disabled user can continue to have full API access. In particular, since that includes account creation, they can create a new account and keep operating even after the JWT expires. ### PoC The issue was validated with version 2.3.3 using the `uozi/nginx-ui:sha-c92ec0a` docker image. View the PoC video: https://github.com/user-attachments/assets/7a5175cb-2f79-4c1b-adad-e7d0bf2ea2bd ### Impact Administrators who rely on "disable user" as an authentication or authorization control can be bypassed. The disabled user can keep reading sensitive configuration and executing authenticated state-changing actions allowed to that account.

CVE-2026-33031 Affected Nginx-UI Versions

1 component(s)
Fixed Versions:
1.9.10-0.20260314152518-7b66578adb47
Product / Package Ecosystem Affected Versions Fixed Version
github.com/0xJacky/Nginx-UI
Go
< 1.9.10-0.20260314152518-7b66578adb47
1.9.10-0.20260314152518-7b66578adb47

References

Frequently Asked Questions

What is CVE-2026-33031?
CVE-2026-33031 is a security vulnerability in Nginx-UI involving Disabled users retain full API access through previously issued bearer tokens under CWE-284: Improper Access Control.
Which Nginx-UI versions are affected?
Affected versions include releases prior to 1.9.10-0.20260314152518-7b66578adb47 across affected packages: github.com/0xJacky/Nginx-UI.
What version fixes CVE-2026-33031?
Upgrading to 1.9.10-0.20260314152518-7b66578adb47 (or the latest patched release for your respective branch) resolves the vulnerability.
Is github.com/0xJacky/Nginx-UI affected?
Yes, github.com/0xJacky/Nginx-UI is affected in releases prior to 1.9.10-0.20260314152518-7b66578adb47. Upgrade your dependency to 1.9.10-0.20260314152518-7b66578adb47 or later.
What is the CVSS score of CVE-2026-33031?
CVE-2026-33031 has a CVSS v3.1 base score of 8.1 (HIGH) with vector string CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N.
What CWE is associated with CVE-2026-33031?
CVE-2026-33031 is classified under CWE-284: Improper Access Control (The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor.).
How can I check Go dependencies for CVE-2026-33031?
Run the dependency tree command: 'inspect dependencies for github.com/0xJacky/Nginx-UI'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-x234-x5vq-cc2v",
  "modified" : "2026-04-27T16:20:27Z",
  "published" : "2026-04-21T15:00:44Z",
  "aliases" : [ "CVE-2026-33031" ],
  "summary" : "Nginx-UI: Disabled users retain full API access through previously issued bearer tokens",
  "details" : "### Summary\n\nA user who was disabled by an administrator can use previously issued API tokens for up to the token lifetime. In practice, disabling a compromised account does not actually terminate that user’s access, so an attacker who already stole a JWT can continue reading and modifying protected resources after the account is marked disabled.\n\nSince tokens can be used to create new accounts, it is possible the disabled user to maintain the privilege.\n\n### Details\n\nThe application exposes an account-level disable control through the users management API. Login process correctly enforces that control:\nhttps://github.com/0xJacky/nginx-ui/blob/6ec542fd97abf2c5950f374f78a32938ad0030e6/internal/user/login.go#L29-L31\n\nHowever, token-based authentication does not enforce the same check (This code validates token structure and expiry, but returns that user object without checking `user.Status`.):\nhttps://github.com/0xJacky/nginx-ui/blob/6ec542fd97abf2c5950f374f78a32938ad0030e6/internal/user/user.go#L44-L139\n\nThere’s also no token revocation feature, unlike when a password is changed:\nhttps://github.com/0xJacky/nginx-ui/blob/6ec542fd97abf2c5950f374f78a32938ad0030e6/api/user/user.go#L38-L51\n\nAs a result, a disabled user can continue to have full API access. In particular, since that includes account creation, they can create a new account and keep operating even after the JWT expires.\n\n### PoC\n\nThe issue was validated with version 2.3.3 using the `uozi/nginx-ui:sha-c92ec0a` docker image.\n\nView the PoC video:\n\n\nhttps://github.com/user-attachments/assets/7a5175cb-2f79-4c1b-adad-e7d0bf2ea2bd\n\n\n\n### Impact\n\nAdministrators who rely on \"disable user\" as an authentication or authorization control can be bypassed.\n\nThe disabled user can keep reading sensitive configuration and executing authenticated state-changing actions allowed to that account.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N"
  }, {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/0xJacky/Nginx-UI"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "1.9.10-0.20260314152518-7b66578adb47"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/0xJacky/nginx-ui/security/advisories/GHSA-x234-x5vq-cc2v"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-33031"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/0xJacky/nginx-ui/commit/7b66578adb47bbec839b621a4666495249379174"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/0xJacky/nginx-ui"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/0xJacky/nginx-ui/releases/tag/v2.3.4"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-284", "CWE-863" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-04-21T15:00:44Z",
    "nvd_published_at" : "2026-04-20T21:16:32Z"
  }
}