CVE-2026-4408

criticalpriority · attend · 50EPSS 0.025 · 85 %ileexploit · PoCDEEURUUS
grimoire priorityP1 · Urgent
Exploitable?
Public exploit
1 exploit · PoC
Likely / severe?
2.50% (85th) EPSS
CVSS 9.8 · critical
Is it mine?
58 products
Check your exposure
Who says so?
4 sources
cnnvd · enisa_euvd · fstec_bdu · cert_bund

EPSS · scored 2026-10-26

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.

01

cvss

Technical severity, 0–10. One row per scoring source.

10.0
010

base score 0–10 · higher = more severe · hover a vector to decode

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 5.9
v3.110criticalAV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU
v3.19criticalCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:Hsecondary · ENISA EU
v3.19criticalCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:Hsecondary · secalert@redhat.com USexploitability 2.2 · impact 6
v3.19criticalCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:Hsecondaryexploitability 2.2 · impact 6
v3.19.3criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:Psecondary · CVSS-BT (t0sche)
02

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: no · Technical Impact: totalcoordinatorcisa_ssvcUS
03

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-78USCWE-78US
04

exploits (1)

Public proof-of-concept and weaponised exploit code.

05

affected products (58)

Products and version ranges known to be affected.

showing 20 of 58
06

advisories (1)

Vendor and ecosystem advisories describing this.

  • WID-SEC-W-2026-1686Samba: Mehrere SchwachstellenDeutsch2026-05-26csaf · cert_bundDE

    Ein Angreifer kann mehrere Schwachstellen in Samba ausnutzen, um beliebigen Programmcode auszuführen, um einen Denial of Service Angriff durchzuführen, um Dateien zu manipulieren, und um Sicherheitsvorkehrungen zu umgehen.

07

also known as (4)

Other names and identifiers for this entity.

08

sources

Which sources assert this record, and when.

cnnvdenisa_euvdfstec_bducert_bundNVDCVE.orgMITRE
published 2026-05-28modified 2026-10-26
09

references (45)

External citations — patches, advisories, analysis.

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