Skip to content
Fencer Intel
medium 5.6

CVE-2025-6533 json

xxyopen/201206030 novel-plus CATCHA LoginController.java ajaxLogin authentication replay

published last yr. modified 4mo ago also EUVD-2025-18961

cvss
5.6
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.6%
EPSS 0.6% chance of exploitation in 30 days, percentile 46%
public exploits
0
none known

Summary

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.

Is CVE-2025-6533 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

Check with Fencer

CISA SSVC

Exploitation
Proof of concept is public
Automatable
no
Technical impact
partial
Assessed
last yr.

Exploit prediction

0.56% chance of exploitation in the next 30 days, higher than 46% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • blog.0xd00.com https://blog.0xd00.com/blog/captcha-replay-attack-lead-to-brute-force-protection-bypass referenced PoC, tagged "exploit" by a source, unverified
  • blog.0xd00.com https://blog.0xd00.com/blog/captcha-replay-attack-lead-to-brute-force-protection-bypass#poc referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 4.0 6.3 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
CNA 3.1 5.6 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P/RL:X/RC:R
CNA 3.0 5.6 CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P/RL:X/RC:R
CNA 2.0 5.1 AV:N/AC:H/Au:N/C:P/I:P/A:P/E:POC/RL:ND/RC:UR
CNA 4.0 2.9 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/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CNA 3.1 5.6 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L
NVD 3.1 5.9 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
CNA 2.0 5.1 AV:N/AC:H/Au:N/C:P/I:P/A:P

Affected products

  • xxyopen novel-plus
  • 201206030 novel-plus

Classification

Weakness
  • CWE-294 Authentication Bypass by Capture-replay
  • CWE-287 Improper Authentication
  • CWE-307 Improper Restriction of Excessive Authentication Attempts

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.