Attack Chain

1. An unauthenticated attacker identifies a Zechat 1.5 instance.
2. The attacker crafts a malicious HTTP GET request targeting the vulnerable v parameter.
3. The crafted request includes a SQL injection payload designed for time-based blind injection.
4. The Zechat application processes the request without proper sanitization of the v parameter, leading to execution of the injected SQL code within the database.
5. The injected SQL code utilizes functions like SLEEP() or similar time-delaying functions to introduce artificial delays based on conditional statements.
6. By observing the response times, the attacker infers the truthiness of the SQL conditions, effectively extracting database information bit by bit.
7. The attacker repeats the process, refining the SQL injection payloads to extract the desired data, such as usernames, passwords, or other sensitive information.
8. The attacker exfiltrates the extracted data from the Zechat database.

Impact

Successful exploitation of this SQL injection vulnerability (CVE-2018-25339) can lead to the complete compromise of the Zechat 1.5 database. This includes potential exposure of user credentials, personal information, and other sensitive data stored within the system. The impact includes data breaches, potential financial loss due to compromised information, and reputational damage to the organization.

Recommendation

• Apply available patches or upgrade to a secure version of Zechat to remediate CVE-2018-25339.
• Deploy the Sigma rule “Detect CVE-2018-25339 Exploitation — Zechat SQL Injection” to your SIEM to detect exploitation attempts.
• Implement input validation and sanitization for all user-supplied data, including the v parameter, to prevent SQL injection attacks.
• Monitor web server logs for suspicious HTTP requests containing SQL injection payloads.