CVE-2026-3100Network attack vector

Backup traffic interception via unchecked TLS certificates

Published Feb 25, 2026 · Updated Feb 25, 2026

Improper certificate validation in ADM FTP Backup 4.1.0 through 4.3.3.ROF1 and 5.0.0 through 5.1.2.RE51 allows attackers to intercept backup traffic. The FTP Backup client does not strictly verify the TLS certificate presented by a configured FTPES or FTPS server, causing an impostor endpoint on the network path to be accepted. Exploitation requires a network-path position and an encrypted remote backup connection; intercepted traffic exposes authentication credentials and backup data to reading or modification.

CVSS severity8.3
High
EPSS probability0.18%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper certificate validation in ADM FTP Backup 4.1.0 through 4.3.3.ROF1 and 5.0.0 through 5.1.2.RE51 allows attackers to intercept backup traffic. The FTP Backup client does not strictly verify the TLS certificate presented by a configured FTPES or FTPS server, causing an impostor endpoint on the network path to be accepted. Exploitation requires a network-path position and an encrypted remote backup connection; intercepted traffic exposes authentication credentials and backup data to reading or modification.

The record

CVE
CVE-2026-3100
Published
Feb 25, 2026
Updated
Feb 25, 2026
Vendor
ASUSTOR Inc.
Product
ASUSTOR Data Master
Classifications
CWE-295, T1557
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 25, 2026CVE publishedPublication date reported by the CVE source.
  2. Feb 25, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=4.1.0 <=4.3.3.ROF1
  2. Affected versionversion=5.0.0 <=5.1.2.RE51

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

ASUSTOR Inc. · ASUSTOR Data Masterversion=4.1.0 <=4.3.3.ROF1; version=5.0.0 <=5.1.2.RE51

Published CVSS scores

6.5NIST NVDCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N
8.3ASUSTOR, Inc.CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-295Improper Certificate Validation
T1557Adversary-in-the-Middle

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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