CVE-2026-18188: data master — Fix

Description

A format string vulnerability was found in the Rsync Backup on the ADM. The vulnerability occurs because user-controlled rsync backup configuration or log data may be processed through an unsafe format string operation. An authenticated attacker can exploit this issue to disclose memory information or cause denial of service of the affected backup component. Affected products and versions include: from ADM 4.1.0 through ADM 4.3.3.RUN1 as well as from ADM 5.0.0 through ADM 5.1.3.RI81.

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CVSS v3.1 Score

8.1

HIGH

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H

EPSS — Exploit Prediction

0.0027

Probability of exploitation

0.18%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-134 CWE-134

Affected Products

Vendor	Product	Versions
asustor	data_master	4.1.0.rhu2 — 4.3.3.run1
asustor	data_master	5.0.0.ra82 — 5.1.4.rjv2

References

Advisories & Patches

https://www.asustor.com/security/security_advisory_detail?id=67

Frequently Asked Questions

What is CVE-2026-18188? +

A format string vulnerability was found in the Rsync Backup on the ADM. The vulnerability occurs because user-controlled rsync backup configuration or log data may be processed through an unsafe format string operation. An authenticated attacker can exploit this issue to disclose memory information or cause denial of service of the affected backup component. Affected products and versions include: from ADM 4.1.0 through ADM 4.3.3.RUN1 as well as from ADM 5.0.0 through ADM 5.1.3.RI81. It has a CVSS v3.1 base score of 8.1 (HIGH).

How severe is CVE-2026-18188? +

CVE-2026-18188 has a CVSS v3.1 score of 8.1 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0027, placing it in the 0th percentile for exploitation probability.

What products are affected by CVE-2026-18188? +

CVE-2026-18188 affects products from asustor, specifically: data_master. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2026-18188? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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CVE-2026-18188