CVE-2026-4408 Details
A flaw was found in Samba. A remote attacker can exploit a misconfiguration in Samba file servers and classic domain controllers that use the "check password script" feature. If this script is configured with the %u substitution character, the client-controlled username is passed without proper escaping of shell meta-characters. This vulnerability allows an attacker to achieve remote command execution on the affected system. This issue primarily affects non-standard configurations where the "check password script" is used with %u and the samba-dcerpcd service is started as a system service.
View at NVD
Exploit prediction scoring system (EPSS) score for CVE-2026-4408
EPSS (Exploit Prediction Scoring System): EPSS predicts the likelihood that a vulnerability will be exploited in the wild. A higher percentage means a greater chance of an exploit occurring. The EPSS model produces a probability score between 0 and 1 (0 and 100%).
2.5 Probability of exploitation activity being observed over the next 30 days (83nd percentile)
CVSS score for CVE-2026-4408
CVSS (Common Vulnerability Scoring System): An open framework owned and managed by FIRST.Org, Inc. that assigns a numerical score from 0 to 10 to software vulnerabilities to indicate their severity.
9 Critical
Products affected by CVE-2026-4408
Samba 4.1.22
Samba 4.1.23
Samba 4.1.6
Samba 4.1.7
Samba 4.1.9
DVE Score by Bitsight AI
DVE scores complement traditional static scoring systems like CVSS with Bitsight AI powered real-time threat intelligence and underground cyber criminal activity so that security teams can reduce alert fatigue and focus on vulnerabilities most likely to be exploited.
Low
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CVE-2026-4408 Global Footprint

Top 10 Identified Countries

Country Observations Percentage
PK 13,942 27.01%
TW 5,659 10.96%
FR 4,245 8.22%
US 2,858 5.54%
DE 2,194 4.25%
IR 2,156 4.18%
RU 1,736 3.36%
ES 1,088 2.11%
GB 1,059 2.05%
CH 914 1.77%

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CVE-2026-4408 Industry Footprint

Top 10 Identified Industries

*Service provider organizations (typically Technology and Telecommunications) are disproportionally represented in the results given their upstream ownership of end-user infrastructure. See our FAQs.

Industry* Observations Percentage
Telecommunications 16,736 65.41%
Technology 8,128 31.77%
Education 162 0.63%
Engineering 120 0.47%
Utilities 119 0.47%
Business Services 91 0.36%
Media/Entertainment 67 0.26%
Government/Politics 41 0.16%
Manufacturing 19 0.07%
Consumer Goods 15 0.06%

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