CVE-2021-42077

Severity: critical (CVSS 9.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 2.5% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2021-11-08 · updated 2026-06-17
Weakness: CWE-89

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.

Affected products

Kaysongroup Php Event Calendar: before 2021-09-03 — fixed in 2021-09-03

How to fix

Upgrade to a fixed version: Kaysongroup Php Event Calendar 2021-09-03. Check the vendor advisory for mitigations.

References

http://packetstormsecurity.com/files/164777/PHP-Event-Calendar-Lite-Edition-SQL-Injection.html
https://www.syss.de/fileadmin/dokumente/Publikationen/Advisories/SYSS-2021-048.txt
http://packetstormsecurity.com/files/164777/PHP-Event-Calendar-Lite-Edition-SQL-Injection.html
https://www.syss.de/fileadmin/dokumente/Publikationen/Advisories/SYSS-2021-048.txt

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