How severe is CVE-2025-6533?

CVE-2025-6533 has a CVSS 3.x base score of 5.6, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.

Is CVE-2025-6533 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (38th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-6533?

CVE-2025-6533 affects Xxyopen Novel-plus. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-6533?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2025-6533 have an EU (EUVD) identifier?

Yes. CVE-2025-6533 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-18961.

When was CVE-2025-6533 published?

CVE-2025-6533 was published on 2025-06-24 and last updated on 2026-06-17.

CVE-2025-6533

CVE-2025-6533 is a medium-severity vulnerability in Xxyopen Novel-plus with a CVSS 3.x base score of 5.6. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-307.

Key facts

Severity: Medium (CVSS 3.x base score 5.6)
CVSS v2: 5.1
CVSS v4: 2.9
EPSS exploit prediction: 0% (38th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-18961
Weakness: CWE-307
Affected product: Xxyopen Novel-plus
Published: 2025-06-24
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2025-6533?: 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.
How severe is CVE-2025-6533?: CVE-2025-6533 has a CVSS 3.x base score of 5.6, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.
Is CVE-2025-6533 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (38th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-6533?: CVE-2025-6533 affects Xxyopen Novel-plus. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-6533?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-6533 have an EU (EUVD) identifier?: Yes. CVE-2025-6533 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-18961.
When was CVE-2025-6533 published?: CVE-2025-6533 was published on 2025-06-24 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:xxyopen:novel-plus:*:*:*:*:*:*:*:*

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