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PatchSiren cyber security CVE debrief

CVE-2016-20070 dwbooster CVE debrief

CVE-2016-20070 is a medium-severity vulnerability (CVSS Score: 5.1) affecting WordPress Booking Calendar Contact Form version 1.0.23. The vulnerability allows authenticated users to escalate privileges and inject malicious scripts due to insufficient verification of user privileges and inadequate sanitization of input parameters. Specifically, attackers with subscriber-level accounts can inject XSS payloads through parameters such as price, name, calendar_language, and email_confirmation_to_user via admin-ajax.php and admin.php endpoints. This enables the execution of arbitrary JavaScript in administrator browsers.

Vendor
dwbooster
Product
Booking Calendar Contact Form
CVSS
MEDIUM 5.1
CISA KEV
Not listed in stored evidence
Original CVE published
2026-06-15
Original CVE updated
2026-06-15
Advisory published
2026-06-15
Advisory updated
2026-06-15

Who should care

Administrators and users of WordPress Booking Calendar Contact Form version 1.0.23 should be aware of this vulnerability. As an authenticated user with a subscriber-level account can exploit this vulnerability, immediate attention is required to prevent potential attacks.

Technical summary

The vulnerability exists due to inadequate validation and sanitization of user input in the WordPress Booking Calendar Contact Form plugin. This allows authenticated users to inject malicious scripts and escalate privileges.

Defensive priority

High

Recommended defensive actions

  • Update WordPress Booking Calendar Contact Form to a version that fixes the vulnerability.
  • Restrict access to the admin-ajax.php and admin.php endpoints.
  • Implement additional security measures to monitor and prevent suspicious activity.

Evidence notes

The CVE record and details were obtained from official sources, including [cve-org](https://www.cve.org/CVERecord?id=CVE-2016-20070) and [nvd](https://nvd.nist.gov/vuln/detail/CVE-2016-20070). Additional information was gathered from [ref-4](http://wordpress.dwbooster.com/), [ref-5](https://www.exploit-db.com/exploits/39423), and [ref-6](https://www.vulncheck.com/advisories/wordpress-booking-calendar-contact-form-privilege-escalation-stored-xss).

Sources and references

Verified primary and authoritative sources

  • CVE-2016-20070 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2016-20070

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2016-20070 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2016-20070

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.