CVE-2026-25993: EverShop Second-Order SQL Injection Flaw

CVE-2026-25993 Overview

CVE-2026-25993 is a critical second-order SQL injection vulnerability affecting EverShop, a TypeScript-first eCommerce platform. The vulnerability exists in the category update and deletion event handling mechanism, where the application embeds path and request_path values—derived from the url_key stored in the database—into SQL statements via string concatenation and passes them to execute(). This design flaw allows attackers to store malicious SQL payloads in the url_key field, which are later executed during subsequent event processing, leading to a classic second-order SQL injection attack.

Critical Impact

Attackers can achieve unauthorized database access, data exfiltration, and potentially complete database compromise by injecting malicious SQL through the url_key field during category or product operations.

Affected Products

• EverShop versions prior to v2.1.1
• EverShop catalog module (category and product services)
• Applications using EverShop's URL rewrite functionality

Discovery Timeline

• February 10, 2026 - CVE-2026-25993 published to NVD
• February 10, 2026 - Last updated in NVD database

Technical Details for CVE-2026-25993

Vulnerability Analysis

This second-order SQL injection vulnerability represents a particularly dangerous attack pattern where malicious input is not executed immediately but stored in the database for later execution. In EverShop's case, the url_key field in the category and product data schemas originally used a permissive regex pattern (^\S+$) that only prevented whitespace characters. This allowed attackers to inject SQL metacharacters and malicious payloads into the url_key field.

When subsequent category update or deletion events occur, the application retrieves the stored url_key value, constructs SQL statements through unsafe string concatenation, and executes them via the execute() function. This deferred execution pattern makes second-order SQL injection particularly difficult to detect and prevent without proper input validation at the data entry point.

Root Cause

The root cause of CVE-2026-25993 lies in insufficient input validation combined with unsafe SQL query construction. The original validation schema for url_key fields used a regex pattern (^\S+$) that only ensured the value contained no whitespace, failing to restrict SQL metacharacters, quotes, or other injection payloads. Additionally, the application used string concatenation rather than parameterized queries when building SQL statements from the stored url_key values during event processing.

Attack Vector

The attack exploits the network-accessible interface of the EverShop platform. An attacker with the ability to create or modify categories or products can inject a malicious SQL payload into the url_key field. Since the original validation only rejected whitespace, payloads containing SQL injection syntax (such as single quotes, semicolons, and SQL commands) would pass validation and be stored in the database. When the application later processes category update or deletion events, it retrieves these malicious values and incorporates them into SQL queries, triggering the injected commands.

The following patch demonstrates the security fix implemented in the category data schema:

     },
     "url_key": {
       "type": "string",
-      "pattern": "^\\S+$",
+      "pattern": "^[a-z0-9]+(?:-[a-z0-9]+)*$",
+      "minLength": 1,
+      "maxLength": 255,
       "errorMessage": {
         "type": "URL key must be a string",
-        "pattern": "URL key cannot contain spaces"
+        "pattern": "URL key must contain only lowercase letters, numbers, and hyphens (e.g., 'my-category-name')",
+        "minLength": "URL key cannot be empty",
+        "maxLength": "URL key cannot exceed 255 characters"
       }
     },
     "status": {

Source: GitHub Commit

The same fix was applied to the product data schema:

     },
     "url_key": {
       "type": "string",
-      "pattern": "^\\S+$",
+      "pattern": "^[a-z0-9]+(?:-[a-z0-9]+)*$",
+      "minLength": 1,
+      "maxLength": 255,
       "errorMessage": {
         "type": "URL key must be a string",
-        "pattern": "URL key cannot contain spaces"
+        "pattern": "URL key must contain only lowercase letters, numbers, and hyphens (e.g., 'my-product-name')",
+        "minLength": "URL key cannot be empty",
+        "maxLength": "URL key cannot exceed 255 characters"
       }
     },
     "meta_title": {

Source: GitHub Commit

Detection Methods for CVE-2026-25993

Indicators of Compromise

• Database entries in category or product tables containing url_key values with SQL metacharacters (single quotes, semicolons, comment sequences like -- or /*)
• Application logs showing SQL syntax errors during category or product update/deletion operations
• Unexpected database modifications or data exfiltration following category management operations
• Anomalous patterns in url_key fields that deviate from standard URL slug formatting

Detection Strategies

• Implement database field auditing to detect url_key values containing non-alphanumeric characters (excluding hyphens)
• Deploy Web Application Firewall (WAF) rules to detect SQL injection patterns in category and product creation/update requests
• Enable database query logging and monitor for anomalous queries originating from the URL rewrite functionality
• Conduct regular database integrity checks to identify potentially malicious stored values

Monitoring Recommendations

• Configure alerts for database errors related to malformed SQL queries in the catalog module
• Monitor API endpoints handling category and product CRUD operations for injection attempt patterns
• Implement real-time log analysis to correlate category management events with unexpected database activity
• Track user sessions that interact with product/category management for suspicious behavior patterns

How to Mitigate CVE-2026-25993

Immediate Actions Required

• Upgrade EverShop to version v2.1.1 or later immediately
• Audit existing database records in category and product tables for malicious url_key values
• Review application logs for evidence of exploitation attempts
• Implement additional input validation at the application layer as defense-in-depth

Patch Information

EverShop has released version v2.1.1 which addresses this vulnerability by implementing strict input validation on the url_key field. The fix replaces the permissive regex pattern with a restrictive pattern (^[a-z0-9]+(?:-[a-z0-9]+)*$) that only allows lowercase letters, numbers, and hyphens. Additional constraints include minimum length of 1 character and maximum length of 255 characters.

For detailed information, refer to the GitHub Security Advisory GHSA-3h84-9rhc-j2ch and the security patch commit.

Workarounds

• If immediate patching is not possible, implement a reverse proxy or WAF rule to reject requests containing SQL injection patterns in url_key fields
• Add database-level constraints or triggers to validate url_key values before storage
• Manually audit and sanitize existing url_key values in the database to remove any potentially malicious content
• Restrict access to category and product management functionality to trusted administrators only

# Database audit query to identify potentially malicious url_key values
# Run this against your EverShop database to detect suspicious entries

SELECT id, url_key FROM category WHERE url_key REGEXP '[^a-z0-9-]';
SELECT id, url_key FROM product WHERE url_key REGEXP '[^a-z0-9-]';

# If suspicious entries are found, sanitize or remove them before upgrading