CVE-2021-39377

CRITICAL

openSIS 8.0 - SQL Injection via index.php username parameter

Title source: llm
STIX 2.1

Exploitation Summary

EIP tracks 1 public exploit for CVE-2021-39377. PoCs published by security-n.

AI-analyzed exploit summary This repository provides a detailed technical writeup of CVE-2021-39377, a SQL injection vulnerability in openSIS 8.0. It includes specific payloads, SQLmap commands, and error-based/time-based injection examples targeting the 'USERNAME' parameter in 'index.php'.

Description

A SQL Injection vulnerability exists in openSIS 8.0 when MySQL (MariaDB) is being used as the application database. A malicious attacker can issue SQL commands to the MySQL (MariaDB) database through the index.php username parameter.

Exploits (1)

nomisec WRITEUP
by security-n · poc
https://github.com/security-n/CVE-2021-39377

This repository provides a detailed technical writeup of CVE-2021-39377, a SQL injection vulnerability in openSIS 8.0. It includes specific payloads, SQLmap commands, and error-based/time-based injection examples targeting the 'USERNAME' parameter in 'index.php'.

Classification
Writeup 90%
Attack Type
Sqli
Complexity
Moderate
Reliability
Reliable
Target: openSIS 8.0
No auth needed
Prerequisites: Access to the vulnerable 'index.php' endpoint · MySQL/MariaDB as the backend database
devstral-2 · analyzed Feb 19, 2026 Full analysis →

References (3)

Core 3
Core References
Third Party Advisory x_refsource_misc
https://github.com/OS4ED/openSIS-Classic
Exploit, Third Party Advisory x_refsource_misc
https://github.com/security-n/CVE-2021-39377
Product x_refsource_misc
https://opensis.com/

Scores

CVSS v3 9.8
EPSS 0.0355
EPSS Percentile 87.8%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Details

CWE
CWE-89
Status published
Products (1)
os4ed/opensis 8.0
Published Sep 01, 2021
Tracked Since Feb 18, 2026