openSIS Classic 9.3 contains an authenticated path traversal vulnerability in the legacy messaging sent-mail attachment download functionality that allows an authenticated attacker to read arbitrary files on the server via crafted path traversal sequences.

OpenSIS 9.2 and below is vulnerable to Incorrect Access Control in Student.php, which allows an authenticated low-privilege user to perform unauthorized database write operations relating to the data of other users.

SQL injection vulnerabilities were discovered in Ajax.php, ForWindow.php, ForExport.php, Modules.php, functions/HackingLogFnc.php in OpenSis Community Edition 9.1 to 8.0, and possibly earlier versions. It is possible for an authenticated user to perform SQL Injection due to the lack to sanitisation. The application takes arbitrary value from "X-Forwarded-For" header and appends it to a SQL INSERT statement directly, leading to SQL Injection.

An SQL Injection vulnerability exists in openSIS Classic 8.0 via the 1) ADDRCONTUSRN, 2) ADDRCONTPSWD, 3) SECNCONTUSRN or 4) SECNCONTPSWD parameters in HoldAddressFields.php.

An SQL Injection vulnerability exists in openSIS Community Edition version 8.0 via ForgotPassUserName.php.

Opensis-Classic Version 8.0 is affected by cross-site scripting (XSS). An unauthenticated user can inject and execute JavaScript code through the linkurl parameter in Ajaxurlencode.php.

Opensis-Classic Version 8.0 is affected by a SQL injection vulnerability due to a lack of sanitization of input data at two parameters $GET['usrid'] and $GET['profid'] in the PasswordCheck.php file.

OS4Ed OpenSIS Community 8.0 is vulnerable to a local file inclusion vulnerability in Modules.php (modname parameter), which can disclose arbitrary file from the server's filesystem as long as the application has access to the file.

A SQL injection vulnerability exists in the Take Attendance functionality of OS4Ed's OpenSIS 8.0. allows an attacker to inject their own SQL query. The cpidmissattn parameter from TakeAttendance.php is vulnerable to SQL injection. An attacker can make an authenticated HTTP request as a user with access to "Take Attendance" functionality to trigger this vulnerability.

OpenSIS Community Edition version 8.0 is affected by a cross-site scripting (XSS) vulnerability in the TakeAttendance.php via the cpidmissattn parameter.

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 ResetUserInfo.php passwordstnid parameter.

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.

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 NamesList.php str parameter.

A SQL injection vulnerability exists in version 8.0 of openSIS when MySQL or MariaDB is used as the application database. An attacker can then issue the SQL command through the index.php USERNAME parameter. NOTE: this issue may exist because of an incomplete fix for CVE-2020-6637.

Eval injection vulnerability in ajax.php in openSIS 4.5 through 5.2 allows remote attackers to execute arbitrary PHP code via the modname parameter.