CVE-2026-2110: Tasin1025 SwiftBuy Auth Bypass Vulnerability

CVE-2026-2110 Overview

A security flaw has been discovered in Tasin1025 SwiftBuy affecting the /login.php file. This vulnerability involves improper restriction of excessive authentication attempts, which could allow attackers to perform brute-force attacks against the login functionality. The vulnerability is remotely exploitable over the network, though the attack complexity is rated as high.

Critical Impact

Attackers can bypass authentication controls through unlimited login attempts, potentially gaining unauthorized access to user accounts through credential brute-forcing.

Affected Products

• Tasin1025 SwiftBuy up to commit 0f5011372e8d1d7edfd642d57d721c9fadc54ec7
• SwiftBuy /login.php authentication endpoint

Discovery Timeline

• 2026-02-07 - CVE-2026-2110 published to NVD
• 2026-02-09 - Last updated in NVD database

Technical Details for CVE-2026-2110

Vulnerability Analysis

This vulnerability falls under CWE-307: Improper Restriction of Excessive Authentication Attempts. The authentication mechanism in SwiftBuy's /login.php fails to implement rate limiting or account lockout policies, allowing unlimited login attempts. While the attack complexity is classified as high, a public exploit has been disclosed, making this vulnerability more accessible to threat actors.

The lack of authentication attempt restrictions creates an opportunity for automated credential stuffing and brute-force attacks. Attackers can systematically test username and password combinations without encountering any blocking mechanisms or delays. This is particularly concerning for applications handling sensitive e-commerce data.

The vendor was contacted about this disclosure but did not respond, and the product follows a rolling release model without versioned security patches.

Root Cause

The root cause of this vulnerability is the absence of rate limiting controls in the authentication flow of /login.php. The application does not track failed login attempts, implement progressive delays, or enforce temporary account lockouts after multiple failed authentication requests. This oversight in security design allows attackers to make unlimited authentication requests without any defensive countermeasures.

Attack Vector

The vulnerability is exploitable remotely over the network (AV:N). An attacker can target the /login.php endpoint with automated tools to perform brute-force or credential stuffing attacks. The attack requires no prior authentication or special privileges, though the complexity is rated as high due to factors that may affect exploit reliability.

The attack flow typically involves:

1. Identifying the target SwiftBuy installation
2. Enumerating valid usernames (if possible)
3. Launching automated credential testing against /login.php
4. Continuously attempting login combinations without restriction
5. Eventually gaining access upon successful credential discovery

For technical details on this vulnerability, refer to the Web Security Insights Post and VulDB Entry #344686.

Detection Methods for CVE-2026-2110

Indicators of Compromise

• Abnormally high volume of POST requests to /login.php from single IP addresses
• Multiple failed authentication attempts in rapid succession
• Suspicious traffic patterns indicating automated credential testing tools
• Successful logins following extended periods of failed attempts from the same source

Detection Strategies

• Implement web application firewall (WAF) rules to detect and alert on excessive login attempts
• Monitor authentication logs for patterns indicative of brute-force attacks
• Set up alerting thresholds for failed login attempts per IP address or user account
• Deploy SIEM correlation rules to identify credential stuffing campaigns

Monitoring Recommendations

• Enable verbose logging on the authentication endpoint to capture all login attempts
• Establish baseline metrics for normal login activity to identify anomalies
• Configure real-time alerts for login attempt volumes exceeding normal thresholds
• Implement geographic-based anomaly detection for login attempts from unusual locations

How to Mitigate CVE-2026-2110

Immediate Actions Required

• Implement rate limiting on the /login.php endpoint immediately
• Deploy a web application firewall (WAF) with brute-force protection rules
• Consider implementing CAPTCHA challenges after a threshold of failed attempts
• Enable account lockout policies after a configurable number of failed attempts
• Review authentication logs for evidence of prior exploitation attempts

Patch Information

No official patch is currently available from the vendor. The vendor was contacted about this disclosure but did not respond. Since SwiftBuy follows a rolling release model, users should monitor the project repository for security-related commits. The vulnerable code exists up to commit 0f5011372e8d1d7edfd642d57d721c9fadc54ec7.

Additional details can be found at:

• VulDB Entry #344686
• VulDB Submission #746251

Workarounds

• Deploy a reverse proxy with rate limiting capabilities in front of the application
• Implement IP-based blocking for sources exceeding login attempt thresholds
• Add multi-factor authentication (MFA) to reduce the impact of compromised credentials
• Consider implementing progressive delays between authentication attempts at the application or infrastructure level

# Example nginx rate limiting configuration for login endpoint
limit_req_zone $binary_remote_addr zone=login:10m rate=5r/m;

location /login.php {
    limit_req zone=login burst=3 nodelay;
    # Additional proxy/fastcgi configuration
}