How severe is CVE-2021-4458?

CVE-2021-4458 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2021-4458 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (27th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-4458?

CVE-2021-4458 affects Webnus Modern Events Calendar Lite. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-4458?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2021-4458 have an EU (EUVD) identifier?

Yes. CVE-2021-4458 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-34683.

When was CVE-2021-4458 published?

CVE-2021-4458 was published on 2025-07-12 and last updated on 2026-06-17.

CVE-2021-4458

CVE-2021-4458 is a medium-severity vulnerability in Webnus Modern Events Calendar Lite with a CVSS 3.x base score of 5.9. 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: Medium (CVSS 3.x base score 5.9)
EPSS exploit prediction: 0% (27th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2021-34683
Weakness: CWE-89
Affected product: Webnus Modern Events Calendar Lite
Published: 2025-07-12
Last modified: 2026-06-17

Description

The Modern Events Calendar Lite plugin for WordPress is vulnerable to SQL Injection via the 'id' parameter of the 'wp_ajax_mec_load_single_page' AJAX action in all versions up to, and including, 6.3.0 due to insufficient escaping on the user supplied parameter and lack of sufficient preparation on the existing SQL query. This makes it possible for unauthenticated attackers to append additional SQL queries into already existing queries that can be used to extract sensitive information from the database. This is only exploitable on sites with addslashes disabled.

Frequently asked questions

What is CVE-2021-4458?: The Modern Events Calendar Lite plugin for WordPress is vulnerable to SQL Injection via the 'id' parameter of the 'wp_ajax_mec_load_single_page' AJAX action in all versions up to, and including, 6.3.0 due to insufficient escaping on the user supplied parameter and lack of sufficient preparation on the existing SQL query. This makes it possible for unauthenticated attackers to append additional SQL queries into already existing queries that can be used to extract sensitive information from the database. This is only exploitable on sites with addslashes disabled.
How severe is CVE-2021-4458?: CVE-2021-4458 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2021-4458 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (27th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-4458?: CVE-2021-4458 affects Webnus Modern Events Calendar Lite. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-4458?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2021-4458 have an EU (EUVD) identifier?: Yes. CVE-2021-4458 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-34683.
When was CVE-2021-4458 published?: CVE-2021-4458 was published on 2025-07-12 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:webnus:modern_events_calendar_lite:*:*:*:*:*:wordpress:*:*

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