Secuno
ENNL
Book demo

CVE-2026-6643

Asustor Data Master remote code execution

9.9 CRITICALEPSS 0.76%
  1. Published20 Apr 2026

Description

A stack-based buffer overflow vulnerability was found in the VPN Clients on the ADM. The issue stems from the use of unbounded sscanf() and passing user-controlled data directly to printf(). Due to the lack of PIE and Stack Canary protections, an authenticated remote attacker can exploit these to execute arbitrary code as the web server user. Affected products and versions include: from ADM 4.1.0 through ADM 4.3.3.RR42 as well as from ADM 5.0.0 through ADM 5.1.2.REO1.

CVSS 3.1 breakdown

Attack vectorNetwork
Attack complexityLow
Privileges requiredLow
User interactionNone
ScopeChanged
ConfidentialityHigh
IntegrityHigh
AvailabilityHigh
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

Affected products

Asustor Data Master≥ 4.1.0.rhu2 < 4.3.3.RR42 · ≥ 5.0.0.ra82 < 5.1.2.reo1

Remediation

Fixed in
Asustor Data Master≥ 4.3.3.RR42

References

Related CVEs

Recent high-severity vulnerabilities sharing a weakness type.

CVE-2026-10910910.0
A vulnerability was detected in Wavlink WL-WN530BE1-A 251117. This vulnerability…
CVE-2026-854578.1
IBM Planning Analytics 2.0, and 2.1 could allow a remote authenticated attacker to…
CVE-2026-962668.2
IBM Power Systems Firmware FW1060.00 through FW1060.81 is affected by a vulnerability…
CVE-2026-962648.2
IBM Power Systems Firmware FW1060.00 through FW1060.81 is affected by a vulnerability…
CVE-2026-962638.2
IBM Power Systems Firmware FW1120.00 through FW1120.01, FW1110.00 through FW1110.31,…
CVE-2026-962628.2
IBM Power Systems Firmware FW1060.00 through FW1060.81 is affected by a vulnerability…

Frequently asked

Is CVE-2026-6643 being actively exploited?

CVE-2026-6643 is not in the CISA KEV catalog. Its EPSS exploit probability is 0.76%.

How severe is CVE-2026-6643?

CVE-2026-6643 has a CVSS 3.1 base score of 9.9, rated critical. EPSS estimates a 0.76% probability of exploitation.

Which products are affected by CVE-2026-6643?

Affected products include Asustor Data Master.

How do I fix CVE-2026-6643?

Upgrade affected software to a fixed version, for example Asustor Data Master 4.3.3.RR42 or later, then confirm no affected versions remain in your inventory.

How Secuno handles this

Secuno correlates vulnerabilities like CVE-2026-6643 against the real software inventory on every managed device, every day. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.

See how prioritisation worksBook a demo

Get Patch this first every Monday

Five vulnerabilities that matter this week, ranked on real exploitation. Plain language, one email, no spam.

You can unsubscribe with one click from every issue. We handle your details as described in our privacy policy.

Data from the NVD, CISA KEV catalog and FIRST EPSS. CVSS 3.1 base score shown where available.