CVE-2026-22235
Published: 08 January 2026
Summary
CVE-2026-22235 is a high-severity Authorization Bypass Through User-Controlled Key (CWE-639) vulnerability in Opexustech Ecase Ecomplaint. Its CVSS base score is 8.7 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 24.0th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified are NIST 800-53 AC-3 (Access Enforcement) and SI-10 (Information Input Validation).
Deeper analysis
CVE-2026-22235 is a vulnerability in OPEXUS eComplaint versions prior to 9.0.45.0 that enables unauthorized access to uploaded files. An attacker can visit the 'DocumentOpen.aspx' endpoint and iterate through predictable values of the 'chargeNumber' parameter to download any files uploaded to the system. This issue stems from CWE-639 (Authorization Bypass Through User-Controlled Key) and carries a CVSS v3.1 base score of 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N), indicating high confidentiality impact.
The vulnerability can be exploited by any unauthenticated remote attacker (PR:N) with low attack complexity (AC:L) and no user interaction (UI:N) required over the network (AV:N). Successful exploitation allows the attacker to achieve high-impact unauthorized access to sensitive uploaded files, potentially exposing confidential data without affecting integrity or availability.
Advisories recommend upgrading to OPEXUS eComplaint version 9.0.45.0 or later to mitigate the vulnerability. Further details are provided in the CISA CSAF advisory at https://raw.githubusercontent.com/cisagov/CSAF/develop/csaf_files/IT/white/2025/va-26-008-02.json and the official CVE record at https://www.cve.org/CVERecord?id=CVE-2026-22235.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-1485
Vulnerability details
OPEXUS eComplaint before version 9.0.45.0 allows an attacker to visit the the 'DocumentOpen.aspx' endpoint, iterate through predictable values of 'chargeNumber', and download any uploaded files.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
The IDOR vulnerability in a public-facing web application directly enables remote unauthenticated file access (T1190) and facilitates retrieval of sensitive data from the local system (T1005).
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
Enforces approved authorizations for access to uploaded files via the 'DocumentOpen.aspx' endpoint, preventing unauthorized downloads through predictable 'chargeNumber' values.
Validates the user-controlled 'chargeNumber' parameter to ensure only authorized file access is permitted, directly addressing the authorization bypass.
Authorizes access decisions to system resources like uploaded files based on applicable policies, mitigating enumeration of predictable identifiers.