CVE-2026-4480: Samba: samba: remote code execution in printing subsystem via unescaped job description

Severity: critical (CVSS 9.0 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 13.9% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2026-05-26 · updated 2026-09-01
Weakness: CWE-78

Description

A flaw was found in the Samba printing subsystem. Samba passes the client-controlled job description string to the command configured with the "print command" setting via the "%J" substitution character without escaping shell meta characters. A remote attacker could exploit this vulnerability by sending a specially crafted print job description that contains unescaped shell characters. This could lead to remote code execution on the affected system.

Affected products

Red Hat Enterprise Linux: 7.0, 8.0, 9.0, 10.0
Red Hat OpenShift Container Platform 4.18: 4.0
Samba: from 4.1.0 before 4.2.1 — fixed in 4.2.1

How to fix

Upgrade to a fixed version: Samba 4.2.1. Check the vendor advisory for mitigations.

References

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