Bug 2454506 (CVE-2026-35386)

Summary: CVE-2026-35386 OpenSSH: OpenSSH: Arbitrary command execution via shell metacharacters in username
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: low Docs Contact:
Priority: low    
Version: unspecifiedCC: adudiak, kshier, stcannon, teagle, yguenane
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in OpenSSH. This vulnerability allows a remote attacker to achieve arbitrary command execution by injecting shell metacharacters into a username provided on the command line. Exploitation requires an untrusted username and a non-default configuration of the '%' character in `ssh_config`.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
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Bug Depends On: 2454961    
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Description OSIDB Bzimport 2026-04-02 18:02:47 UTC
In OpenSSH before 10.3, command execution can occur via shell metacharacters in a username within a command line. This requires a scenario where the username on the command line is untrusted, and also requires a non-default configurations of % in ssh_config.