CVE-2026-49221

Executive Summary

CVE-2026-49221 is an access control vulnerability (CWE-639: Authorization Bypass Through User-Controlled Key) in Vvveb CMS versions prior to 1.0.8.4. A low-privileged Vendor account can access, modify, or delete digital assets belonging to other Vendors’ products due to insufficient enforcement of ownership boundaries on a caller-controlled digital_asset_id parameter. The vulnerability affects all Vvveb installations that expose the backend product management interface to authenticated Vendor users in versions before 1.0.8.4. Exploitation results in high confidentiality impact (disclosure of private product metadata and asset names), high integrity impact (corruption of resource links and tampering with asset metadata), and high availability impact (deletion of asset records causing data loss), reflected in the CVSS score of 8.8.

Technical Analysis

The flaw resides in the identifier-based authorization pattern of Vvveb's backend digital asset management workflow. The NVD description identifies two specific controllers — admin/controller/product/digital-asset.php and admin/controller/product/digital-assets.php — along with the SQL query file admin/sql/sqlite/digital_asset.sql. These components handle list, read, edit, and delete operations for digital assets. The controllers accept a caller-supplied digital_asset_id parameter and perform database queries against the digital asset table without consistently joining or filtering on the admin_id of the currently authenticated session.

The vulnerability class is CWE-639 (Authorization Bypass Through User-Controlled Key). The server-side code uses a primary key (digital_asset_id) as the sole trust boundary for authorization decisions. In a correctly hardened implementation, each query would include an additional predicate such as WHERE admin_id = :current_user_id AND digital_asset_id = :requested_id to scope the record access to the authenticated user's own assets. Based on the description, such a predicate is either absent entirely or applied inconsistently across the four operations (list, read, edit, delete). This creates an Insecure Direct Object Reference (IDOR) condition where any authenticated Vendor can supply arbitrary digital_asset_id values to enumerate and operate on records owned by other Vendors.

Note: The description does not specify whether the SQLite backend uses transactions or whether the controllers sanitize the identifier. Insufficient technical detail is available regarding the exact query structure beyond the role of the digital_asset_id parameter and the missing admin_id boundary enforcement. The attack surface is the authenticated backend web interface, requiring network access to the application and a valid Vendor-level credential.

Exploitation Scenarios

No public PoC or exploit code is available as of this writing; the attack chain below is inferred from the vulnerability class (CWE-639) and the description of the affected operations.

Step 1 — Reconnaissance / Target Identification: An attacker who already possesses a low-privileged Vendor account (e.g., someone who created a trial vendor profile or obtained credentials via phishing or credential stuffing) identifies a target Vvveb installation. The attacker logs into the backend and navigates to the product digital asset management page, which triggers the affected digital-asset.php or digital-assets.php controller. The attacker notes the structure of legitimate asset IDs in their own vendor space by listing their own assets, which reveals the URL parameter format (e.g., ?digital_asset_id=123).

Step 2 — Triggering the Flaw Class: The attacker begins incremental enumeration of digital_asset_id values outside their own legitimate set. Since the backend fails to enforce the admin_id ownership boundary, each request with a different digital_asset_id returns the asset record associated with that ID regardless of which Vendor created it. This is a direct trigger of the IDOR condition — the attacker manipulates a user-controlled key (the digital asset identifier) to reference objects outside their authorized scope.

Step 3 — Payload / Execution Method: At the vulnerability-class level, the attack uses HTTP GET or POST requests to the affected backend controllers with manipulated identifier parameters. For example:

• Listing assets: request the digital assets list endpoint with a range of IDs to enumerate all assets in the system.
• Reading assets: issue requests for specific digital_asset_id values to retrieve asset names and file metadata.
• Editing assets: submit modification requests (typically POST with form data) to alter metadata fields of another Vendor's asset, potentially changing the asset description, file association, or visibility settings.
• Deleting assets: issue delete requests with target IDs to remove asset records.

The attacker does not need to craft a malicious payload beyond the manipulated identifier — the flaw is purely in the authorization check, not in input handling or injection.

Step 4 — Post-Exploitation Impact: Successful exploitation yields:

• Confidentiality breach: Disclosure of private product metadata, asset file names, file formats, sizes, and other metadata that are not intended for cross-vendor visibility. This can reveal business plans, unreleased product details, or partner-confidential information.
• Integrity compromise: Corruption of resource links by editing metadata or reassociating assets, which can break product pages, cause front-end display errors, or redirect customers to unintended files. An attacker could also overwrite metadata to mislabel a legitimate asset.
• Availability impact: Deletion of asset records, leading to data loss for competing Vendors. Since deleted assets may be permanently removed from the SQLite database, this could require manual restoration from backups, potentially causing downtime or permanent loss if no backups exist. If the attacker deletes a large number of asset records programmatically, the damage escalates to a business-disrupting incident.

Impact Assessment

The CVSS vector (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H) yields a base score of 8.8, placing this in the High severity band. Key drivers of the score include:

• Attack Vector: Network (AV:N) — Exploitation requires only network access to the Vvveb web interface; no physical or local access is needed.
• Attack Complexity: Low (AC:L) — No special conditions are required to exploit the flaw; standard HTTP requests suffice.
• Privileges Required: Low (PR:L) — The attacker needs only a Vendor-level account, which is a standard role in multi-vendor CMS deployments. This is a significant concern because Vendor accounts are lower-trust than Administrator accounts.
• User Interaction: None (UI:N) — No victim action is needed for successful exploitation.
• Scope: Unchanged (S:U) — The compromise is confined to the database records accessed via the affected component.

Affected Systems: All Vvveb CMS installations running versions prior to 1.0.8.4 that have the backend product management module enabled and that issue Vendor accounts. Multi-tenant deployments where multiple Vendors manage products on a single instance are at highest risk.

Blast Radius: The vulnerability allows cross-Vendor access. In a single-vendor installation, the impact is limited because there is only one Vendor; however, in e-commerce or marketplace deployments where Vvveb serves as the platform for multiple third-party Vendors, the blast radius is broad — a single compromised Vendor account can impact all other Vendors' data. Confidentiality loss alone could expose proprietary product information to competitors hosting stores on the same platform.

Business Impact: High. The combination of data disclosure, data corruption, and data deletion can tarnish platform trust, lead to legal liability for data loss, cause revenue loss from broken product pages, and result in reputational damage. The administrative overhead of investigating and restoring deleted/modified assets further aggravates the impact.

Detection Guidance

Sigma Rule

title: Vvveb Cross-Vendor Digital Asset Access Attempt
id: 7f3c2a1e-9b4d-4f6c-8d2a-1a5e3b9c7d01
status: experimental
description: Detects anomalous enumeration or modification patterns targeting Vvveb digital asset controllers indicative of CVE-2026-49221 exploitation.
references:
    - https://nvd.nist.gov/vuln/detail/CVE-2026-49221
author: Valtersit Threat Intel
date: 2026/04/11
logsource:
    category: webserver
    product: generic
detection:
    selection:
        cs-uri-base|contains:
            - 'admin/controller/product/digital-asset.php'
            - 'admin/controller/product/digital-assets.php'
        cs-method:
            - 'GET'
            - 'POST'
    filter_legitimate:
        cs-uri-base|contains: 'digital-asset'
        sc-status: 200
        # NOTE: Baseline SOC analysts should tune with normal user behavior patterns
    condition: selection and not filter_legitimate
    timeframe: 5m
level: high
tags:
    - attack.t1213
    - cve.2026.49221

YARA Rule

rule Vvveb_CVE_2026_49221_Asset_IDOR_Enumeration
{
    meta:
        author = "Valtersit Threat Intel"
        description = "Detects HTTP request patterns consistent with CVE-2026-49221 digital asset IDOR exploitation"
        cve = "CVE-2026-49221"
        date = "2026-04-11"
        severity = "high"
    strings:
        $s1 = "digital-asset.php" ascii wide nocase
        $s2 = "digital-assets.php" ascii wide nocase
        $s3 = "digital_asset_id=" ascii wide nocase
        $s4 = "action=delete" ascii wide nocase
        $s5 = "action=edit" ascii wide nocase
        $s6 = "action=list" ascii wide nocase
        $s7 = "admin" ascii wide nocase
    condition:
        any of ($s1, $s2) and $s3 and 1 of ($s4, $s5, $s6) and $s7
}

Suricata IDS Rule

alert http any any -> $HOME_NET any (
    msg:"CVE-2026-49221 Vvveb Digital Asset IDOR Attempt";
    flow:established,to_server;
    http.uri;
    content:"admin/controller/product/digital-asset"; http_uri;
    content:"digital_asset_id"; http_uri;
    pcre:"/digital[_\-]asset(?:s)?\.php.*digital_asset_id=\d{1,6}/Ui";
    metadata:attack_target Web_Server;
    reference:cve,2026-49221;
    classtype:attempted-user;
    sid:950021;
    rev:1;
)

Note: This signature may generate false positives in legitimate use cases where a single user manages multiple assets with sequential IDs within a short time frame. Tune by whitelisting known Vendor IP ranges or adding a threshold of distinct IDs per session.

Elastic Detection

sequence by source.ip with maxspan=15m
  [network where event.type == "connection" and destination.port == 80 or destination.port == 443]
  [http where http.request.method in ("GET", "POST") and
      string(http.request.uri) like "*digital-asset*.php*"
      and string(http.request.uri) like "*digital_asset_id*"
      and http.response.status_code == 200]
  [http where http.request.method in ("GET", "POST") and
      string(http.request.uri) like "*digital-asset*.php*"
      and string(http.request.uri) like "*digital_asset_id*"
      and http.response.status_code == 200]
  [http where http.request.method in ("GET", "POST") and
      string(http.request.uri) like "*digital-asset*.php*"
      and string(http.request.uri) like "*digital_asset_id*"
      and http.response.status_code == 200
      and sid != null]
  | stats count(request_count) by source.ip
  where request_count > 10

Splunk SPL Query

index=web sourcetype=access_combined
| where match(uri, "(?i)digital-asset[s]?\.php") AND match(uri, "digital_asset_id:")
| eval asset_id = extract_digit(uri, "digital_asset_id")
| stats count by src_ip, asset_id, uri
| where count > 10
| eval alert_message = "Potential CVE-2026-49221 IDOR exploitation from " . src_ip . " - " . count . " unique asset requests"
| table _time, src_ip, count, asset_id, uri

Wazuh OSSEC Rule

<group name="vvveb,idor,cve-2026-49221,">
  <rule id="100921" level="12">
    <decoded_as>web-access-log</decoded_as>
    <field name="url">\.php.*digital_asset_id=</field>
    <field name="url">digital-asset</field>
    <description>Vvveb CVE-2026-49221: Access to digital-asset controller with manipulated asset ID</description>
    <group>exploit_attempt</group>
    <mitre>
      <id>T1213</id>
    </mitre>
    <options>no_full_log</options>
  </rule>
</group>

Mitigation & Patch Guidance

Patch Confidence: 0/4 — UNPATCHED — no patch evidence from any tracked source.

Immediate Mitigations:

1. Limit Vendor account exposure: If active Vendor accounts are not required, disable the Vendor role or restrict its permissions to read-only for product management.
2. Implement WAF rules: Deploy web application firewall rules that block requests to digital-asset.php and digital-assets.php where digital_asset_id values exceed a baseline range (indicating enumeration attempts).
3. Restrict network access: Apply IP allowlisting on the backend administrative interface so that only corporate/office IP ranges can access the admin panel.
4. Disable backend access to Vendor accounts: If the multi-vendor feature is not actively used, revoke Vendor role assignments and re-assign affected users to a minimal role that lacks access to the product controllers.

Patch / Upgrade Steps:

1. Upgrade to Vvveb 1.0.8.4 or later — this version contains the fix for the digital asset ownership boundary issue. The upgrade is the definitive remediation.
2. If upgrade is not immediately possible: Manually patch the two affected controllers (admin/controller/product/digital-asset.php and admin/controller/product/digital-assets.php) to include an explicit admin_id WHERE clause in every SQL query that handles digital asset operations, and ensure the digital_asset.sql file's queries likewise incorporate the session's admin_id as an additional predicate. Also validate that digital_asset_id is an integer and rejects non-numeric input.
3. Verify database integrity: After patching, audit the digital_asset table for orphaned or tampered records and restore from backups if necessary.

Long-Term Hardening:

1. Adopt an authorization framework: Refactor backend controllers to use a centralized authorization layer that enforces object-level permissions based on the authenticated session, rather than relying on per-query WHERE clauses.
2. Implement logging and alerting: Enable detailed audit logging on all backend CRUD operations, capturing the authenticated user, the asset ID accessed, and the action performed. Alert on anomalies such as a single user accessing a high volume of unique asset IDs.
3. Conduct regular code review: Establish a security review process for all database queries that accept caller-controlled identifiers, checking for consistent ownership scoping.
4. Apply principle of least privilege: Ensure Vendor accounts have only the minimum permissions required for their role and that backend endpoints are categorized by privilege level.

References

1. NVD Entry: https://nvd.nist.gov/vuln/detail/CVE-2026-49221 — Official NVD record containing the description, CVSS score, and CWE classification.
2. Vvveb Official Site / Changelog: https://www.vvveb.com/ — Vendor project page; version 1.0.8.4 release notes should indicate the security fix for this issue (note: no public advisory was retrievable as of this report).
3. CWE-639 Reference: https://cwe.mitre.org/data/definitions/639.html — MITRE definition of Authorization Bypass Through User-Controlled Key, the underlying weakness class.
4. CISA KEV Catalog: https://www.cisa.gov/known-exploited-vulnerabilities-catalog — This CVE is NOT listed in the KEV catalog as of the publication date; no known exploit-in-the-wild evidence has been documented by CISA.
5. Nuclei Templates (Monitoring): https://github.com/projectdiscovery/nuclei-templates — No template for CVE-2026-49221 exists as of this writing; SOCs should monitor this repository for future additions.

Threat Actor Campaigns: No threat actor campaigns or exploit-in-the-wild activity have been publicly reported for CVE-2026-49221 at this time. The vulnerability is rated 8.8 (High) and its unpatched status makes it a valid target for opportunistic attackers; organizations using Vvveb in multi-vendor deployments should treat it as an active threat.