{
    "document": {
        "category": "csaf_base",
        "csaf_version": "2.0",
        "distribution": {
            "tlp": {
                "label": "WHITE"
            }
        },
        "lang": "en",
        "notes": [
            {
                "category": "legal_disclaimer",
                "text": "The Netherlands Cyber Security Center (henceforth: NCSC-NL) maintains this portal to enhance access to its information and vulnerabilities. The use of this information is subject to the following terms and conditions:\n\nThe vulnerabilities disclosed in this portal are gathered by NCSC-NL from a variety of open sources, which the user can retrieve from other platforms. NCSC-NL makes every reasonable effort to ensure that the content of this portal is kept up to date, and that it is accurate and complete. Nevertheless, NCSC-NL cannot entirely rule out the possibility of errors, and therefore cannot give any warranty in respect of its completeness, accuracy or real-time keeping up-to-date. NCSC-NL does not control nor guarantee the accuracy, relevance, timeliness or completeness of information obtained from these external sources. The vulnerabilities disclosed in this portal are intended solely for the convenience of professional parties to take appropriate measures to manage the risks posed to the cybersecurity. No rights can be derived from the information provided therein.\n\nNCSC-NL and the Kingdom of the Netherlands assume no legal liability or responsibility for any damage resulting from either the use or inability of use of the vulnerabilities disclosed in this portal. This includes damage resulting from the inaccuracy of incompleteness of the information contained in it.\nThe information on this page is subject to Dutch law. All disputes related to or arising from the use of this portal regarding the disclosure of vulnerabilities will be submitted to the competent court in The Hague. This choice of means also applies to the court in summary proceedings."
            }
        ],
        "publisher": {
            "category": "coordinator",
            "contact_details": "cert@ncsc.nl",
            "name": "National Cyber Security Centre",
            "namespace": "https://www.ncsc.nl/"
        },
        "title": "CVE-2026-34989",
        "tracking": {
            "current_release_date": "2026-04-03T04:48:05.522323Z",
            "generator": {
                "date": "2026-02-17T15:00:00Z",
                "engine": {
                    "name": "V.E.L.M.A",
                    "version": "1.7"
                }
            },
            "id": "CVE-2026-34989",
            "initial_release_date": "2026-04-03T04:39:41.823378Z",
            "revision_history": [
                {
                    "date": "2026-04-03T04:39:41.823378Z",
                    "number": "1",
                    "summary": "CVE created.| Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| References created (2).| CWES updated (1)."
                },
                {
                    "date": "2026-04-03T04:39:46.480282Z",
                    "number": "2",
                    "summary": "NCSC Score created."
                }
            ],
            "status": "interim",
            "version": "2"
        }
    },
    "vulnerabilities": [
        {
            "cve": "CVE-2026-34989",
            "cwe": {
                "id": "CWE-79",
                "name": "Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')"
            },
            "notes": [
                {
                    "category": "description",
                    "text": "## Summary\n### **Vulnerability 1: Stored DOM XSS via Profile Name Update (Persistent Payload Injection)**\n- Stored Cross-Site Scripting via Unsanitized User Name in Profile Management\n\n### Description\nThe application fails to properly sanitize user-controlled input when users update their profile name (e.g., full name / username). An attacker can inject a malicious JavaScript payload into their profile name, which is then stored server-side.\n\nThis stored payload is later rendered unsafely in multiple application views without proper output encoding, leading to stored cross-site scripting (XSS).\n\n### Affected Functionality\n- Profile name / full name update functionality (both the 2 user inputs)\n- User profile storage and retrieval logic\n\n### Attack Scenario\n- An attacker updates their profile 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 name is rendered in affected views.\n\n### Impact\n- Persistent Stored XSS\n- Execution of arbitrary JavaScript in victims’ browsers\n- Foundation for privilege escalation and account takeover when viewed by privileged users & normal ones across blogs and public facing pages that show user profiles full names\n\nEndpoint: `/backend/users/profile/`\n\n### **Vulnerability 2: Stored XSS via User Name Rendering Across Multiple Endpoints (Privilege Escalation)**\n(Required for the chain)\n- Stored XSS via Unsafe Rendering of User Names Across Administrative and Public Interfaces\n\n### Description\nUser-controlled profile fields (specifically the username / full name) are rendered unsafely across multiple application endpoints, including administrative and content-related interfaces. The application fails to apply proper output encoding when displaying these values.\n\nWhen an administrator accesses affected pages, the stored XSS payload executes in the administrator’s browser context, resulting in administrative privilege escalation and potential full admin account takeover.\n\nThis issue is not limited to a single endpoint and affects all areas where the username is rendered, including but not limited to:\n- User management interfaces\n- Blog pages\n- Other content or UI components displaying usernames\n\n### Attack Scenario\n- Attacker injects a malicious payload via the profile name update functionality.\n- The payload is stored persistently.\n- An administrator views the user management page or any affected interface.\n- The payload executes automatically in the admin’s browser.\n- Attacker hijacks the admin session, performs privileged actions, or fully compromises the admin account.\n\n### Impact\n- Stored XSS\n- Administrative privilege escalation\n- Full admin account takeover (including other roles)\n- Full compromise of the entire application\n\nEndpoint Example: `/backend/users/` of User Management Page\n\n## Steps To Reproduce (POC)\n1. Go to Profile Management page of the User\n2. In the 2 user inputs of the Full Name, put in any field of them a XSS Payload such as:\n`<img src=x onerror=alert(document.domain)>`\n3. Save the edit\n4. Go to User Management page as an Admin or any other role\n5. Notice the XSS alert popping up that confirms it\n6. Other endpoints aswell can execute such as blogs in the public facing one \n\n### Recommended Remediation\n\n1. **Eliminate Unsafe DOM Sinks:** Remove all usage of `.html()`, `innerHTML`, and similar unsafe DOM manipulation methods throughout the application. These sinks should be replaced with safe alternatives such as `.text()` or `textContent`, which do not interpret HTML markup.\n\n2. **Implement Output Encoding:** Apply context-appropriate HTML entity encoding to all user-controlled data before rendering it in the DOM. This ensures that any special characters (e.g., `<`, `>`, `\"`, `'`) are rendered as literal text rather than interpreted as executable markup.\n\n3. **Implement Server-Side Input Sanitization:** Enforce strict input validation and sanitization on all user-controlled fields — particularly the profile name fields — at the server level before storing values in the database. Currently, no sanitization is applied to these inputs.\n\n4. **Apply Defense in Depth:** Even in cases where user input does not appear to flow directly into a dangerous sink, it should still be treated as untrusted. Attackers can and will leverage indirect data flows to exploit the application. A layered approach combining input validation, output encoding, and Content Security Policy (CSP) headers is strongly recommended.\n# Ready Video POC:\nhttps://mega.nz/file/iEVEyT4Y#f046o6ZwYBfS1kK0HNKOCFm6tL_8_SbLtWWKC1hYC4M",
                    "title": "github - https://api.github.com/advisories/GHSA-vr2g-rhm5-q4jr"
                },
                {
                    "category": "other",
                    "text": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H",
                    "title": "CVSSV4"
                },
                {
                    "category": "other",
                    "text": "9.4",
                    "title": "CVSSV4 base score"
                },
                {
                    "category": "other",
                    "text": "4.1",
                    "title": "NCSC Score"
                },
                {
                    "category": "other",
                    "text": "The value of the most recent CVSS (V4) score, Is related to CWE-269 (Improper Privilege Management)",
                    "title": "NCSC Score top increasing factors"
                }
            ],
            "references": [
                {
                    "category": "external",
                    "summary": "Source - github",
                    "url": "https://api.github.com/advisories/GHSA-vr2g-rhm5-q4jr"
                },
                {
                    "category": "external",
                    "summary": "Reference - github",
                    "url": "https://github.com/ci4-cms-erp/ci4ms/security/advisories/GHSA-vr2g-rhm5-q4jr"
                },
                {
                    "category": "external",
                    "summary": "Reference - github",
                    "url": "https://github.com/advisories/GHSA-vr2g-rhm5-q4jr"
                }
            ],
            "title": "CVE-2026-34989"
        }
    ]
}