{
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "CI4MS is a CodeIgniter 4-based CMS skeleton that delivers a production-ready, modular architecture with RBAC authorization and theme support. Prior to version 0.31.0.0, the application fails to properly sanitize user-controlled input when creating or editing blog tags. An attacker can inject a malicious JavaScript payload into the tag name field, which is then stored server-side. This stored payload is later rendered unsafely across public tag pages and administrative interfaces without proper output encoding, leading to stored cross-site scripting (XSS). This issue has been patched in version 0.31.0.0."
    }
  ],
  "id": "CVE-2026-34559",
  "lastModified": "2026-04-03T16:10:52.680",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "LOW",
          "baseScore": 9.1,
          "baseSeverity": "CRITICAL",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "LOW",
          "privilegesRequired": "LOW",
          "scope": "CHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:L",
          "version": "3.1"
        },
        "exploitabilityScore": 3.1,
        "impactScore": 5.3,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ]
  },
  "published": "2026-04-01T22:16:18.780",
  "references": [
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/ci4-cms-erp/ci4ms/releases/tag/0.31.0.0"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/ci4-cms-erp/ci4ms/security/advisories/GHSA-4333-387x-w245"
    },
    {
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "url": "https://github.com/ci4-cms-erp/ci4ms/security/advisories/GHSA-4333-387x-w245"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Undergoing Analysis",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-79"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Secondary"
    }
  ]
}

{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 0.28.6.0"
      },
      "package": {
        "ecosystem": "Packagist",
        "name": "ci4-cms-erp/ci4ms"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.31.0.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-34559"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-79"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-04-01T21:53:01Z",
    "nvd_published_at": "2026-04-01T22:16:18Z",
    "severity": "CRITICAL"
  },
  "details": "## Summary\n### **Vulnerability: Stored DOM XSS via Blog Tag Name (Persistent Payload Injection)**\n- Stored Cross-Site Scripting via Unsanitized Blog Tag Name in Blog Management\n\n### Description\nThe application fails to properly sanitize user-controlled input when creating or editing blog tags. An attacker can inject a malicious JavaScript payload into the tag name field, which is then stored server-side.\n\nThis stored payload is later rendered unsafely across public tag pages and administrative interfaces without proper output encoding, leading to stored cross-site scripting (XSS).\n\n### Affected Functionality\n- Blog tag creation functionality\n- Blog tag editing functionality\n- Blog tag storage and retrieval logic\n\n### Attack Scenario\n- An attacker creates or edits a blog tag name to include a malicious XSS payload.\n- The application stores this value without sanitization or encoding.\n- The payload persists and executes whenever the tag name is rendered in affected views.\n\n### Impact\n- Persistent Stored XSS\n- Execution of arbitrary JavaScript in victims\u2019 browsers\n- Privilege escalation when viewed by administrators or privileged users\n- Full administrator account takeover\n- Full account takeover across all roles\n- Full compromise of the entire application\n\nEndpoints:\n- `/backend/blogs/tags/`\n- `/blog/{id}`\n\n## Steps To Reproduce (POC)\n1. Go to the Blog Tags management page\n2. Create or edit a tag and insert an XSS payload into the tag name such as:\n`\u003cimg src=x onerror=alert(document.domain)\u003e`\n3. Save the tag\n4. View a public blog page or the administrative interface where the tag is rendered\n5. Notice the XSS payload executing automatically\n\n## Remediation\n\n- **Avoid unsafe DOM manipulation methods:** Do not use `.html()`, `innerHTML`, or similar sink functions in client-side JavaScript or server-side templating (e.g., PHP). Even when user input flowing into these sinks is not immediately apparent, they can introduce Cross-Site Scripting (XSS) vulnerabilities that an attacker may exploit.\n\n- **Apply output encoding:** Implement HTML entity encoding on all user-controlled data before rendering it in the browser. This helps neutralize potentially malicious input.\n\n- **Implement input sanitization:** Ensure that all user-supplied input is properly sanitized before processing or output. Currently, no sanitization mechanisms are in place, which should be addressed as a priority.\n\n- **Enforce security headers and cookie attributes:**\n  - **Content Security Policy (CSP):** Define and enforce a strict CSP to limit the execution of unauthorized scripts.\n  - **HttpOnly flag:** Set the `HttpOnly` attribute on session cookies to prevent client-side script access.\n  - **SameSite attribute:** Configure the `SameSite` cookie attribute to mitigate Cross-Site Request Forgery (CSRF) risks.\n  - **Secure flag:** Ensure all cookies are transmitted only over HTTPS by enabling the `Secure` attribute.\n\n  These measures collectively reduce the impact of XSS and help prevent escalation paths such as CSRF via XSS.\n# Ready Video POC:\nhttps://mega.nz/file/GI9Bnbha#FkVY4K7AiuttnBGDFaCtxuJwKk-afRcKjYJnkqfLZOM",
  "id": "GHSA-4333-387x-w245",
  "modified": "2026-04-06T17:13:49Z",
  "published": "2026-04-01T21:53:01Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/ci4-cms-erp/ci4ms/security/advisories/GHSA-4333-387x-w245"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-34559"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/ci4-cms-erp/ci4ms"
    },
    {
      "type": "WEB",
      "url": "https://github.com/ci4-cms-erp/ci4ms/releases/tag/0.31.0.0"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:L",
      "type": "CVSS_V3"
    }
  ],
  "summary": "CI4MS: Blogs Tags Full Account Takeover for All-Roles \u0026 Privilege-Escalation via Stored DOM XSS"
}