CVE-2021-40309

Name: CVE-2021-40309
Creator: NVD / NIST
Published: 2021-09-24T16:15:08.417+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 8.8/10EPSS 1.76%

Last modified Jun 17, 2026

CVE-2021-40309 is a high-severity vulnerability rated 8.8/10 on the CVSS scale. 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. EPSS estimates a 1.76% chance of exploitation in the next 30 days.

Description

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 cp_id_miss_attn 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.

Metrics

CVSS 3.1

8.8/10

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS Probability

1.76%

75.2th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-89

Affected Software

Vendor	Product	Versions
Os4ed	Opensis	8.0

References

https://github.com/MiSERYYYYY/Vulnerability-Reports-and-Disclosures/blob/main/OpenSIS-Community-8.0.mdExploit, Third Party Advisory
https://github.com/OS4ED/openSIS-ClassicProduct, Third Party Advisory
https://www.exploit-db.com/exploits/50249Exploit, Third Party Advisory, VDB Entry
https://github.com/MiSERYYYYY/Vulnerability-Reports-and-Disclosures/blob/main/OpenSIS-Community-8.0.mdExploit, Third Party Advisory
https://github.com/OS4ED/openSIS-ClassicProduct, Third Party Advisory
https://www.exploit-db.com/exploits/50249Exploit, Third Party Advisory, VDB Entry

Timeline

Published: Sep 24, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-40309?

How severe is CVE-2021-40309?

CVE-2021-40309 has a CVSS score of 8.8/10 (HIGH severity). The EPSS model estimates a 1.76% probability of exploitation in the next 30 days.

How do I fix CVE-2021-40309?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-40309?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST