CVE-2026-40523 FrontAccounting SQL Injection in Audit Trail – High Severity Patch Required

Technical summary

The vulnerability exists in the Audit Trail report handler where user input in the PARAM_2 and PARAM_3 POST parameters is concatenated into SQL queries without proper sanitization or parameterized query use. An authenticated attacker can leverage both UNION-based injection (to extract data) and time-based blind injection via SLEEP() functions amplified across multiple JOIN operations. The SLEEP amplification technique is particularly dangerous: a single sleep command repeated across a large result set (e.g., thousands of rows) can quickly exhaust database connection pools and trigger denial of service.

Business impact

Compromise of this vulnerability allows unauthorized data exfiltration of financial records, customer information, or other sensitive data stored in the FrontAccounting database. Denial of service attacks can render the accounting system unavailable, blocking invoice generation, payment processing, and financial reporting. In regulated industries, a data breach may trigger notification obligations and compliance penalties. Operational continuity is at risk if database connections are exhausted during business hours.

Affected systems

FrontAccounting installations running versions prior to 2.4.20 are affected. The vulnerability requires the attacker to possess or obtain credentials for a user account with the SA_GLANALYTIC permission (Analytical report access). No specific operating systems or deployment architectures are inherently more vulnerable; risk depends on whether the application is internet-accessible and how broadly the SA_GLANALYTIC role is assigned.

Exploitability

Exploitability is high for insiders or attackers who have obtained valid credentials. The attack requires no special network position (network-accessible), involves no client-side interaction, and uses standard SQL injection techniques that are well-understood and easily automated. However, the attacker must first gain authentication and specifically hold the SA_GLANALYTIC permission, which limits the potential attacker pool compared to unauthenticated vulnerabilities. The SLEEP-based DoS variant is simple to execute and effective at scale.

Remediation

Upgrade FrontAccounting to version 2.4.20 or later. This version addresses the SQL injection by implementing parameterized queries or input validation in the Audit Trail report handler. If immediate patching is not feasible, restrict the SA_GLANALYTIC permission to only essential staff, monitor for unusual report queries, and consider implementing Web Application Firewall rules to detect SQL injection patterns in POST parameters targeting the Audit Trail endpoint.

Patch guidance

Verify the availability of FrontAccounting 2.4.20 or later through the official FrontAccounting project repository or vendor advisory. Review release notes to confirm SQL injection remediation is included. Test the patched version in a non-production environment against your reporting workflows before production deployment. Document the patched version in your asset inventory. If using a managed hosting provider, confirm they have applied or will apply the patch on your behalf.

Detection guidance

Monitor database query logs for unusual SLEEP() functions, UNION SELECT statements, or multi-line SQL in audit trail report requests. Check Web Application Firewall or proxy logs for POST requests to the Audit Trail report endpoint containing SQL keywords or comment characters (-- /* */) in PARAM_2 or PARAM_3. Review database connection pool exhaustion events correlated with reports accessed by users with SA_GLANALYTIC rights. Audit access logs to identify which accounts hold SA_GLANALYTIC permission and verify their necessity.

Why prioritize this

This vulnerability scores 8.1 (HIGH) because it enables both confidentiality breach (data exfiltration) and availability impact (DoS via connection exhaustion) with low attack complexity and low privilege requirements relative to the sensitive data an accounting system holds. Although authentication is required, SA_GLANALYTIC is not an admin role, expanding the potential attacker pool beyond DBAs. The widespread use of SQL injection techniques and the clarity of the attack path warrant rapid patching, especially if the application is internet-facing or accessible to untrusted networks.

Risk score, explained

CVSS 3.1 score of 8.1 reflects: Attack Vector (Network) – FrontAccenting can be web-accessible; Attack Complexity (Low) – standard SQL injection; Privileges Required (Low) – authenticated user with a non-admin role; User Interaction (None) – direct parameter manipulation; Scope (Unchanged) – impact limited to the database; Confidentiality (High) – arbitrary SQL queries permit data exfiltration; Integrity (None) – the CVE does not document write capability; Availability (High) – SLEEP-amplified DoS exhausts connections. The HIGH severity reflects the combination of data breach and DoS potential in a financial system context.

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