How severe is CVE-2026-3100?

CVE-2026-3100 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity low, and availability none.

Is CVE-2026-3100 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (8th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-3100?

CVE-2026-3100 affects Asustor Data Master. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-3100?

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

Does CVE-2026-3100 have an EU (EUVD) identifier?

Yes. CVE-2026-3100 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-8516.

When was CVE-2026-3100 published?

CVE-2026-3100 was published on 2026-02-25 and last updated on 2026-06-17.

CVE-2026-3100

CVE-2026-3100 is a medium-severity vulnerability in Asustor Data Master with a CVSS 3.x base score of 6.5. 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-295.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v4: 8.3
EPSS exploit prediction: 0% (8th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-8516
Weakness: CWE-295
Affected product: Asustor Data Master
Published: 2026-02-25
Last modified: 2026-06-17

Description

The FTP Backup on the ADM will not properly strictly enforce TLS certificate verification while connecting to an FTP server using FTPES/FTPS. An improper validated TLS/SSL certificates allows a remote attacker can intercept network traffic to perform a Man-in-the-Middle (MitM) attack, which may intercept, modify, or obtain sensitive information such as authentication credentials and backup data. Affected products and versions include: from ADM 4.1.0 through ADM 4.3.3.ROF1 as well as from ADM 5.0.0 through ADM 5.1.2.RE51.

Frequently asked questions

What is CVE-2026-3100?: The FTP Backup on the ADM will not properly strictly enforce TLS certificate verification while connecting to an FTP server using FTPES/FTPS. An improper validated TLS/SSL certificates allows a remote attacker can intercept network traffic to perform a Man-in-the-Middle (MitM) attack, which may intercept, modify, or obtain sensitive information such as authentication credentials and backup data. Affected products and versions include: from ADM 4.1.0 through ADM 4.3.3.ROF1 as well as from ADM 5.0.0 through ADM 5.1.2.RE51.
How severe is CVE-2026-3100?: CVE-2026-3100 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity low, and availability none.
Is CVE-2026-3100 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (8th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-3100?: CVE-2026-3100 affects Asustor Data Master. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-3100?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-3100 have an EU (EUVD) identifier?: Yes. CVE-2026-3100 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-8516.
When was CVE-2026-3100 published?: CVE-2026-3100 was published on 2026-02-25 and last updated on 2026-06-17.

References

https://www.asustor.com/security/security_advisory_detail?id=53

Affected products (1)

cpe:2.3:o:asustor:data_master:*:*:*:*:*:*:*:*

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