How severe is CVE-2021-36621?

CVE-2021-36621 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-36621 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (79th percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2021-36621?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-36621 published?

CVE-2021-36621 was published on 2021-07-30 and last updated on 2026-06-17.

CVE-2021-36621

CVE-2021-36621 is a high-severity vulnerability in Online Covid Vaccination Scheduler System Project Online Covid Vaccination Scheduler System with a CVSS 3.x base score of 8.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-89.

Key facts

Severity: High (CVSS 3.x base score 8.1)
CVSS v2: 6.8
EPSS exploit prediction: 2% (79th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-89
Affected product: Online Covid Vaccination Scheduler System Project Online Covid Vaccination Scheduler System
Published: 2021-07-30
Last modified: 2026-06-17

Description

Sourcecodester Online Covid Vaccination Scheduler System 1.0 is vulnerable to SQL Injection. The username parameter is vulnerable to time-based SQL injection. Upon successful dumping the admin password hash, an attacker can decrypt and obtain the plain-text password. Hence, the attacker could authenticate as Administrator.

Frequently asked questions

What is CVE-2021-36621?: Sourcecodester Online Covid Vaccination Scheduler System 1.0 is vulnerable to SQL Injection. The username parameter is vulnerable to time-based SQL injection. Upon successful dumping the admin password hash, an attacker can decrypt and obtain the plain-text password. Hence, the attacker could authenticate as Administrator.
How severe is CVE-2021-36621?: CVE-2021-36621 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-36621 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (79th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-36621?: CVE-2021-36621 affects Online Covid Vaccination Scheduler System Project Online Covid Vaccination Scheduler System. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-36621?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-36621 published?: CVE-2021-36621 was published on 2021-07-30 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:online_covid_vaccination_scheduler_system_project:online_covid_vaccination_scheduler_system:1.0:*:*:*:*:*:*:*

More vulnerabilities in Online Covid Vaccination Scheduler System Project Online Covid Vaccination Scheduler System

CVE-2021-36622 — Critical (CVSS 9.8): Sourcecodester Online Covid Vaccination Scheduler System 1.0 is affected vulnerable to Arbitrary File Upload. The admin…
CVE-2021-37803 — High (CVSS 8.1): An SQL Injection vulnerability exists in Sourcecodester Online Covid Vaccination Scheduler System 1.0 via the username…
CVE-2021-41930 — Medium (CVSS 6.1): Cross site scripting (XSS) vulnerability in Sourcecodester Online Covid Vaccination Scheduler System v1 by oretnom23,…

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