CVE-2021-42077
CVSS v3
9.8
CRITICAL
EPSS Score
2.5 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
—
SSVC status
Description
PHP Event Calendar before 2021-09-03 allows SQL injection, as demonstrated by the /server/ajax/user_manager.php username parameter. This can be used to execute SQL statements directly on the database, allowing an adversary in some cases to completely compromise the database system. It can also be used to bypass the login form.
Technical details
- Published
- 2021-11-08
Frequently asked questions
What is CVE-2021-42077?
PHP Event Calendar before 2021-09-03 allows SQL injection, as demonstrated by the /server/ajax/user_manager.php username parameter. This can be used to execute SQL statements directly on the database, allowing an adversary in some cases to completely compromise the database system. It can also be used to bypass the login form.
Is CVE-2021-42077 actively exploited?
Active exploitation of CVE-2021-42077 has not been confirmed. Its EPSS score was 2.5% on 2026-09-25, the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2021-42077?
CVE-2021-42077 has a CVSS v3 base score of 9.8 (CRITICAL severity).
Is CVE-2021-42077 affecting your environment?
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