{"cve":"CVE-2021-42663","nvd":{"published":"2021-11-05T13:15:07.630","modified":"2026-06-17T04:09:55.850","status":"Modified","description":"An HTML injection vulnerability exists in Sourcecodester Online Event Booking and Reservation System in PHP/MySQL via the msg parameter to /event-management/index.php. An attacker can leverage this vulnerability in order to change the visibility of the website. Once the target user clicks on a given link he will display the content of the HTML code of the attacker's choice.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N","score":4.3},"cwes":["CWE-79"],"references":["https://github.com/TheHackingRabbi/CVE-2021-42663","https://www.sourcecodester.com/php/14241/online-event-booking-and-reservation-system-phpmysql.html","https://github.com/TheHackingRabbi/CVE-2021-42663","https://www.sourcecodester.com/php/14241/online-event-booking-and-reservation-system-phpmysql.html"],"products":["online_event_booking_and_reservation_system_project:online_event_booking_and_reservation_system"],"source":"nvd","synced_at":"2026-10-19T21:24:39.218183596+00:00"},"epss":{"cve":"CVE-2021-42663","score":0.03852,"percentile":0.90145,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}