CVE-2021-42662

MEDIUM

Sourcecodester Online Event Booking and Reservation System - Stored Cross-Site Scripting via Holiday Reason Parameter

Title source: llm
STIX 2.1

Exploitation Summary

EIP tracks 3 public exploits for CVE-2021-42662. PoCs published by Alon Leviev, 0xDeku.

AI-analyzed exploit summary This exploit demonstrates a stored XSS vulnerability in the 'reason' parameter of the Online Event Booking and Reservation System 1.0. The payload is injected via a POST request to the holiday endpoint, leading to arbitrary JavaScript execution in the context of the victim's browser.

Description

A Stored Cross Site Scripting (XSS) vulnerability exists in Sourcecodester Online Event Booking and Reservation System in PHP/MySQL via the Holiday reason parameter. An attacker can leverage this vulnerability in order to run javascript commands on the web server surfers behalf, which can lead to cookie stealing and more.

Exploits (3)

exploitdb WORKING POC
by Alon Leviev · textwebappsphp
https://www.exploit-db.com/exploits/50450

This exploit demonstrates a stored XSS vulnerability in the 'reason' parameter of the Online Event Booking and Reservation System 1.0. The payload is injected via a POST request to the holiday endpoint, leading to arbitrary JavaScript execution in the context of the victim's browser.

Classification
Working Poc 95%
Attack Type
Xss
Complexity
Trivial
Reliability
Reliable
Target: Online Event Booking and Reservation System 1.0
No auth needed
Prerequisites: Access to the vulnerable web application · Ability to submit a POST request to the holiday endpoint
MITRE ATT&CK
devstral-2 · analyzed Feb 16, 2026 Full analysis →
nomisec WORKING POC 2 stars
by 0xDeku · poc
https://github.com/0xDeku/CVE-2021-42662

This repository contains a proof-of-concept for CVE-2021-42662, a stored XSS vulnerability in the Online Event Booking and Reservation System version 2.3.0. The exploit leverages the 'reason' parameter in the HOLY page to execute arbitrary JavaScript code.

Classification
Working Poc 90%
Attack Type
Xss
Complexity
Trivial
Reliability
Reliable
Target: Online Event Booking and Reservation System 2.3.0
No auth needed
Prerequisites: Access to the vulnerable web application
MITRE ATT&CK
devstral-2 · analyzed Feb 16, 2026 Full analysis →
inthewild WRITEUP
poc
https://github.com/thehackingrabbi/cve-2021-42662

This repository provides a technical description and proof-of-concept for a stored XSS vulnerability in the Online Event Booking and Reservation System version 2.3.0. The vulnerability allows an attacker to inject malicious JavaScript via the 'reason' parameter on the HOLY page.

Classification
Writeup 90%
Attack Type
Xss
Complexity
Trivial
Reliability
Reliable
Target: Online Event Booking and Reservation System version 2.3.0
No auth needed
Prerequisites: Access to the vulnerable page · Ability to submit a crafted payload
devstral-2 · analyzed Feb 23, 2026 Full analysis →

References (4)

Core 4
Core References
Exploit, Third Party Advisory x_refsource_misc
https://github.com/TheHackingRabbi/CVE-2021-42662
Exploit, Third Party Advisory, VDB Entry x_refsource_misc
https://www.exploit-db.com/exploits/50450

Scores

CVSS v3 5.4
EPSS 0.0223
EPSS Percentile 84.9%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

Details

CWE
CWE-79
Status published
Products (1)
online_event_booking_and_reservation_system_project/online_event_booking_and_reservation_system 2.3.0
Published Nov 05, 2021
Tracked Since Feb 18, 2026