CVE-2021-40261 in Automated Enrollment System
Summary
by MITRE • 11/09/2021
Multiple Cross Site Scripting (XSS) vulnerabilities exist in SourceCodester CASAP Automated Enrollment System 1.0 via the (1) user_username and (2) category parameters in save_class.php, the (3) firstname, (4) class, and (5) status parameters in student_table.php, the (6) category and (7) class_name parameters in add_class1.php, the (8) fname, (9) mname,(10) lname, (11) address, (12) class, (13) gfname, (14) gmname, (15) glname, (16) rship, (17) status, (18) transport, and (19) route parameters in add_student.php, the (20) fname, (21) mname, (22) lname, (23) address, (24) class, (25) fgname, (26) gmname, (27) glname, (28) rship, (29) status, (30) transport, and (31) route parameters in save_stud.php,the (32) status, (33) fname, and (34) lname parameters in add_user.php, the (35) username, (36) firstname, and (37) status parameters in users.php, the (38) fname, (39) lname, and (40) status parameters in save_user.php, and the (41) activity_log, (42) aprjun, (43) class, (44) janmar, (45) Julsep,(46) octdec, (47) Students and (48) users parameters in table_name.
If you want to get best quality of vulnerability data, you may have to visit VulDB.
Analysis
by VulDB Data Team • 11/11/2021
The CVE-2021-40261 vulnerability represents a critical cross site scripting flaw affecting the SourceCodester CASAP Automated Enrollment System version 1.0, exposing multiple entry points where user-supplied input is inadequately sanitized before being rendered in web responses. This vulnerability falls under CWE-79 which specifically addresses cross site scripting conditions where untrusted data is improperly incorporated into web pages served to users. The flaw manifests across numerous php endpoints including save_class.php, student_table.php, add_class1.php, add_student.php, save_stud.php, add_user.php, users.php, save_user.php, and table_name.php, indicating a systemic issue in input validation and output encoding practices throughout the application's codebase. The vulnerability's impact is amplified by the fact that it affects parameters handling user credentials, personal information, academic records, and system administrative data.
The technical exploitation of this vulnerability occurs when attackers inject malicious javascript payloads through the identified parameters, which are then executed in the context of other users' browsers who access the affected pages. The attack vectors span across user registration fields, student personal information, class enrollment details, and administrative status updates, creating multiple potential attack surfaces for threat actors. Each vulnerable parameter represents a distinct pathway for attackers to establish persistent malicious presence within the system, potentially leading to session hijacking, data exfiltration, or privilege escalation. The vulnerability's scope extends beyond simple script execution as it affects both frontend user interfaces and backend administrative panels, making it particularly dangerous for educational institutions managing sensitive student and staff data.
The operational impact of CVE-2021-40261 is severe given that the affected system manages automated enrollment processes for educational institutions, making it a prime target for attackers seeking to compromise student records and institutional data integrity. The vulnerability enables attackers to potentially steal user sessions, redirect victims to malicious sites, or inject malware through compromised browser contexts. This risk is particularly elevated in educational environments where systems contain sensitive personal information, academic records, and potentially financial data. The vulnerability's presence in administrative interfaces like add_user.php and users.php also raises concerns about privilege escalation and unauthorized system access, as attackers could manipulate user accounts and gain elevated privileges within the enrollment system. The ATT&CK framework categorizes this vulnerability under T1059.007 for scripting languages and T1566.001 for spearphishing with a link, as attackers could leverage these XSS flaws to deliver malicious payloads to unsuspecting users.
Mitigation strategies for CVE-2021-40261 must focus on implementing comprehensive input validation and output encoding mechanisms across all affected endpoints. The primary remediation involves sanitizing all user-supplied input through proper encoding functions such as htmlspecialchars() and implementing Content Security Policy headers to prevent unauthorized script execution. The system should also employ parameterized queries and proper input validation frameworks to ensure that all parameters are validated against expected data types and ranges. Organizations should conduct thorough code reviews to identify and remediate similar vulnerabilities across the entire application codebase, as the presence of multiple XSS flaws suggests a broader architectural security issue. Additionally, implementing web application firewalls and regular security testing including automated scanning and manual penetration testing will help prevent exploitation of these vulnerabilities. The remediation process should also include proper user education about the risks of clicking suspicious links and the importance of maintaining updated system configurations to prevent attackers from leveraging these vulnerabilities in combination with other exploits.