CVE intelligence and bounded remediation

CVE-2021-42077 — PHP Event Calendar before 2021-09-03 allows SQL injection, as demonstrated by the /server/ajax/user_manager.php username parameter

Critical CVSS 9.8

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.

Severity
Critical
CVSS
9.8 (3.1)
Published
2021-11-08
CISA KEV
Not currently listed
Ecosystem
software/application
Weaknesses
CWE-89

Affected products

  • kaysongroup / php_event_calendar

Matched remediation archetype

SQL and data-query injection

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Check exposure

  • Trace request, message, file, and stored values into SQL, ORM query fragments, filters, sort expressions, and other data-query languages.
  • Inventory database roles, reachable schemas, multi-tenant boundaries, and whether stacked or administrative operations are enabled.
  • Check both direct queries and second-order use of previously stored values.

Remediate safely

  • Use parameterized queries or safe query builders for all values; map identifiers and operators through explicit allowlists.
  • Remove raw query concatenation and give the application account only the tables and operations it requires.
  • Update affected data-access components and add regression tests for query structure preservation with inert edge-case inputs.

Authoritative sources

Complete CVE record and remediation plan

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