Web Application Vulnerabilities: Real-World Exploitation and Security Lessons
A series of recent technical write-ups and research articles highlight the ongoing risks posed by web application vulnerabilities, including source code disclosure, SQL injection, and insecure direct object references (IDOR). One case study demonstrates how a shopping website's backup files, accessible via a hidden directory, exposed sensitive source code and hard-coded database credentials due to improper directory listing and robots.txt configuration. Another firsthand account details a significant financial loss after a modern Spring Boot application suffered a SQL injection attack, bypassing ORM protections and security audits, which allowed an attacker to manipulate discount codes and process fraudulent transactions. These incidents underscore that even contemporary, well-maintained applications remain susceptible to classic vulnerabilities when security controls are inconsistently applied or overlooked.
In addition to these real-world breaches, a technical explainer on IDOR vulnerabilities outlines why such flaws persist in modern API-driven environments, emphasizing the challenges of reliably enforcing object-level authorization. The article explains how IDORs often arise from overlooked workflow edges and inconsistent ownership validation, making them difficult to detect with standard security testing. Collectively, these reports serve as a reminder that legacy vulnerabilities like SQL injection and IDOR continue to threaten organizations, and that secure coding practices, comprehensive testing, and vigilant configuration management are essential to mitigating these risks.
Timeline
Jan 2, 2026
Backup directory exposed Java source code and hardcoded PostgreSQL credentials
A shopping website's accessible /backup directory, discoverable by fuzzing and referenced in robots.txt, had directory listing enabled and exposed a java.bak file. The backup file disclosed Java source code containing hardcoded PostgreSQL credentials for a local database instance.
Dec 31, 2025
Organization remediated SQL injection incident and overhauled security
Following the attack, the organization implemented strict input validation, removed native queries, disabled multi-statement execution, added security tests, and conducted a full code audit. It also hired a dedicated security engineer and enforced security checklists in code reviews.
Dec 31, 2025
Attackers abused SQL injection to alter discounts and cause $47,000 in fraud
Attackers exploited the vulnerable discount search to dump discount codes, modify discount percentages, and apply 100% discounts to hundreds of orders. The incident resulted in about $47,000 in fraudulent transactions, along with reputational damage and scrutiny from payment processors.
Dec 31, 2025
SQL injection flaw exposed admin discount search in Spring Boot app
A modern Spring Boot application had a SQL injection vulnerability in a native SQL query used by an admin discount code search feature. The endpoint was misconfigured to be publicly accessible and lacked proper input validation, reintroducing a classic injection flaw despite use of JPA and Hibernate.
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