CVE-2025-26523: RupeeWeb Auth Bypass Vulnerability

CVE-2025-26523 Overview

CVE-2025-26523 affects the RupeeWeb trading platform. The vulnerability stems from insufficient authorization controls on API endpoints that handle addition and deletion operations. An authenticated remote attacker can abuse these endpoints to modify information belonging to other user accounts.

The issue is categorized as Broken Access Control and tracked under [CWE-266] (Incorrect Privilege Assignment). CERT-IN published this vulnerability in advisory CIVN-2025-0020. Successful exploitation results in horizontal privilege escalation across tenant accounts on the trading platform.

Critical Impact
Authenticated attackers can modify or delete data tied to other users on the RupeeWeb trading platform, exposing financial information to unauthorized tampering.

Affected Products

RupeeWeb trading platform (web application)
API endpoints handling addition operations
API endpoints handling deletion operations

Discovery Timeline

2025-02-14 - CVE-2025-26523 published to NVD
2026-06-17 - Last updated in NVD database
Reference - CERT-IN Vulnerability Note CIVN-2025-0020

Technical Details for CVE-2025-26523

Vulnerability Analysis

The RupeeWeb platform exposes API endpoints that accept add and delete operations from authenticated users. These endpoints fail to verify whether the requesting user owns the targeted resource. The server trusts identifiers supplied in the request and acts on them without an ownership check.

This class of flaw is known as Insecure Direct Object Reference (IDOR) and falls under broken access control. An attacker who holds a valid account can substitute another user's resource identifier in API calls. The backend then performs the requested mutation against records that belong to a different account.

The vulnerability requires high privileges to exploit, meaning the attacker must hold a valid authenticated session on the platform. The attack vector is network-based, and no user interaction from the victim is required.

Root Cause

The root cause is missing object-level authorization on mutating API endpoints. The application authenticates the session but does not authorize the operation against the target object. Resource identifiers passed as parameters are processed without a server-side check that ties the object to the session's user identifier.

Attack Vector

An attacker first authenticates to RupeeWeb with valid credentials. The attacker then enumerates or guesses resource identifiers belonging to other accounts. By issuing crafted POST or DELETE requests against the vulnerable endpoints with the target identifiers, the attacker can add or remove data tied to other users. The vulnerability is described in the CERT-IN advisory CIVN-2025-0020. No public proof-of-concept code is available.

Detection Methods for CVE-2025-26523

Indicators of Compromise

Unexpected creation or deletion of records on user accounts that did not initiate the action
API calls where the authenticated session identifier does not match the owner of the referenced resource identifier
Burst patterns of sequential resource identifiers in add or delete API requests from a single session
User complaints regarding altered trading records, watchlists, or account data

Detection Strategies

Enable verbose API access logging on the RupeeWeb platform, capturing user identifier, resource identifier, and operation
Compare the session user identifier against the owner of the referenced resource for every mutating request
Alert on anomalous ratios of cross-user object references in add and delete endpoints
Review CERT-IN advisory CIVN-2025-0020 for vendor-supplied indicators

Monitoring Recommendations

Forward web server and API gateway logs to a centralized SIEM for correlation
Track per-account modification rates and flag spikes that exceed normal user behavior
Monitor authentication events alongside subsequent API mutations to identify low-and-slow abuse
Establish a baseline for normal add and delete volumes per user and alert on deviations

How to Mitigate CVE-2025-26523

Immediate Actions Required

Contact the RupeeWeb vendor to confirm patch availability and apply remediation as soon as it is released
Restrict access to the trading platform to known IP ranges where business requirements allow
Audit historical API logs for evidence of cross-account add or delete operations
Reset session tokens and force re-authentication on the platform if abuse is suspected

Patch Information

As of the latest NVD update on 2026-06-17, refer to CERT-IN advisory CIVN-2025-0020 for vendor remediation guidance. Apply the fixed version of RupeeWeb supplied by the vendor as soon as it is available. Verify that object-level authorization checks are present on every mutating endpoint after patching.

Workarounds

Implement a reverse proxy or web application firewall (WAF) rule set to inspect identifiers in add and delete requests against the authenticated session
Disable or rate-limit affected API endpoints until a vendor patch is deployed
Enforce stricter session controls, including short session lifetimes and multi-factor authentication for trading accounts
Conduct manual review of recent account changes for high-value users until remediation is confirmed

bash

# Example WAF rule concept (ModSecurity-style) to log cross-account references
# Replace placeholders with deployment-specific variables.
SecRule REQUEST_URI "@rx /api/(add|delete)" \
    "id:1026523,phase:2,log,pass,\
    msg:'RupeeWeb mutating API call - verify ownership',\
    chain"
    SecRule ARGS:user_id "!@streq %{SESSION.user_id}" \
        "t:none,deny,status:403"