How severe is CVE-2025-68435?

CVE-2025-68435 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.

Is CVE-2025-68435 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (28th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-68435?

CVE-2025-68435 primarily affects Nicotsx Zerobyte. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2025-68435?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

Does CVE-2025-68435 have an EU (EUVD) identifier?

Yes. CVE-2025-68435 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-204006.

When was CVE-2025-68435 published?

CVE-2025-68435 was published on 2025-12-17 and last updated on 2026-06-17.

CVE-2025-68435

CVE-2025-68435 is a critical-severity vulnerability in Nicotsx Zerobyte with a CVSS 3.x base score of 9.1. 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-305.

Key facts

Severity: Critical (CVSS 3.x base score 9.1)
EPSS exploit prediction: 0% (28th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-204006
Weakness: CWE-305
Affected product: Nicotsx Zerobyte
Published: 2025-12-17
Last modified: 2026-06-17

Description

Zerobyte is a backup automation tool Zerobyte versions prior to 0.18.5 and 0.19.0 contain an authentication bypass vulnerability where authentication middleware is not properly applied to API endpoints. This results in certain API endpoints being accessible without valid session credentials. This is dangerous for those who have exposed Zerobyte to be used outside of their internal network. A fix has been applied in both version 0.19.0 and 0.18.5. If immediate upgrade is not possible, restrict network access to the Zerobyte instance to trusted networks only using firewall rules or network segmentation. This is only a temporary mitigation; upgrading is strongly recommended.

Frequently asked questions

What is CVE-2025-68435?: Zerobyte is a backup automation tool Zerobyte versions prior to 0.18.5 and 0.19.0 contain an authentication bypass vulnerability where authentication middleware is not properly applied to API endpoints. This results in certain API endpoints being accessible without valid session credentials. This is dangerous for those who have exposed Zerobyte to be used outside of their internal network. A fix has been applied in both version 0.19.0 and 0.18.5. If immediate upgrade is not possible, restrict network access to the Zerobyte instance to trusted networks only using firewall rules or network segmentation. This is only a temporary mitigation; upgrading is strongly recommended.
How severe is CVE-2025-68435?: CVE-2025-68435 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2025-68435 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (28th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-68435?: CVE-2025-68435 primarily affects Nicotsx Zerobyte. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2025-68435?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2025-68435 have an EU (EUVD) identifier?: Yes. CVE-2025-68435 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-204006.
When was CVE-2025-68435 published?: CVE-2025-68435 was published on 2025-12-17 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:nicotsx:zerobyte:*:*:*:*:*:*:*:*
cpe:2.3:a:nicotsx:zerobyte:0.19.0:beta1:*:*:*:*:*:*

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