CVE-2026-57821: Apache Fineract SQL Injection Vulnerability

CVE-2026-57821 Overview

CVE-2026-57821 is a SQL Injection vulnerability in Apache Fineract's Office Search API (GET /api/v1/offices) affecting versions up to and including 1.14.0. The orderBy request parameter is concatenated into a SQL query without sufficient validation. An authenticated user with permission to view offices can inject arbitrary SQL through a crafted orderBy value. This flaw bypasses the ColumnValidator fix introduced for CVE-2024-32838, which does not detect bare subqueries in the ORDER BY position. Attackers can leverage the issue for time-based blind SQL injection and concurrent exploitation can exhaust the database connection pool.

Critical Impact
Authenticated attackers can exfiltrate sensitive database contents via time-based blind SQL injection and trigger denial of service by exhausting the application's database connection pool.

Affected Products

Apache Fineract versions up to and including 1.14.0
Deployments exposing the GET /api/v1/offices endpoint
Instances relying solely on the CVE-2024-32838 ColumnValidator mitigation

Discovery Timeline

2026-07-15 - CVE-2026-57821 published to the National Vulnerability Database (NVD)
2026-07-15 - Last updated in NVD database

Technical Details for CVE-2026-57821

Vulnerability Analysis

The vulnerability is a classic SQL Injection flaw [CWE-89] in Apache Fineract's office listing endpoint. The orderBy query parameter accepted by GET /api/v1/offices is concatenated directly into the generated SQL statement. The prior fix for CVE-2024-32838 added a ColumnValidator intended to restrict column identifiers, but the validator does not recognize bare subqueries placed in the ORDER BY clause. As a result, an attacker who is authenticated and holds the office-view permission can supply a subquery payload that the database will execute.

Because the endpoint returns rows without reflecting query results, attackers rely on time-based blind techniques. Payloads use functions such as database-specific sleep operations wrapped in conditional expressions to leak data one bit at a time. Each injected query holds a database connection open for the duration of the timing delay. When multiple requests run concurrently, the connection pool is quickly exhausted, denying service to legitimate users.

Root Cause

The root cause is insufficient allow-list validation of user-supplied ordering identifiers. The ColumnValidator introduced for CVE-2024-32838 checks known patterns but fails to reject standalone subqueries. String concatenation, rather than parameterization, is used when constructing the ORDER BY clause, permitting arbitrary SQL to reach the database.

Attack Vector

Exploitation requires network access to the Fineract API and valid credentials with permission to view offices. The attacker issues an HTTP GET request to /api/v1/offices with a malicious orderBy value containing a subquery. Refer to the Apache Fineract security patch pull request and the Apache mailing list advisory for technical details on the injected payload structure and validator bypass.

Detection Methods for CVE-2026-57821

Indicators of Compromise

Requests to GET /api/v1/offices containing suspicious orderBy values with parentheses, SELECT, SLEEP, PG_SLEEP, BENCHMARK, or CASE WHEN tokens.
Repeated authenticated requests to the offices endpoint with abnormally long response times.
Database connection pool exhaustion alerts correlating with traffic to /api/v1/offices.
Application logs showing SQL parsing errors originating from the office search handler.

Detection Strategies

Deploy web application firewall (WAF) rules that flag SQL keywords and subquery syntax inside the orderBy parameter of Fineract API calls.
Monitor database query logs for ORDER BY clauses containing nested SELECT statements against the m_office table.
Correlate authenticated API activity with unusually high query latency to identify time-based blind injection attempts.

Monitoring Recommendations

Track connection pool utilization metrics and alert on sustained saturation events.
Log full request URIs and query parameters for /api/v1/offices requests to support forensic review.
Baseline typical orderBy values used by legitimate clients and alert on deviations.

How to Mitigate CVE-2026-57821

Immediate Actions Required

Upgrade Apache Fineract to a version containing the fix as referenced in the official pull request.
Audit user accounts with office-view permissions and revoke unnecessary access.
Review recent access logs for the /api/v1/offices endpoint to identify prior exploitation attempts.

Patch Information

The Apache Fineract project has merged a fix that strengthens validation of the orderBy parameter to reject subqueries. Consult the Apache mailing list thread and the security patch pull request for the exact fixed version and upgrade guidance. All deployments running 1.14.0 or earlier are affected and should be upgraded.

Workarounds

Restrict network access to the /api/v1/offices endpoint via reverse proxy allow-lists until patching is complete.
Deploy WAF signatures that block orderBy values containing parentheses or SQL keywords.
Tighten role-based access control (RBAC) so only trusted administrators can query offices.
Configure database connection pool timeouts and per-query execution limits to reduce denial-of-service impact.

bash

# Example WAF rule (ModSecurity) to block suspicious orderBy values
SecRule REQUEST_URI "@beginsWith /api/v1/offices" \
  "chain,phase:2,deny,status:400,id:1057821,msg:'Potential SQLi in Fineract orderBy'"
  SecRule ARGS:orderBy "@rx (?i)(select|sleep|benchmark|pg_sleep|case\s+when|\(|--)" \
    "t:none,t:urlDecodeUni"