CVE-2026-94140

Rex versions through 1.16.1 for Perl accept an unknown SSH host key for remote rsync transfers because sync hardcodes StrictHostKeyChecking=no. Every remote branch of sync builds its ssh command with that option, for password authentication, for private-key authentication and for the fallback. The ssh options a caller sets through set_openssh_opt reach the OpenSSH transport but not this command, so there is no configuration that restores host key checking for the transfer. An attacker who can redirect the connection before the real host key is known presents their own and the transfer proceeds: under password authentication sync sends the connection password to that server, an upload writes the selected local files to it, and a download writes what it returns to the local destination.

CVSS v3 9.1 CRITICAL

9.1^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://metacpan.org/release/FERKI/Rex-1.16.1/source/lib/Rex/Commands/Rsync.pm
http://www.openwall.com/lists/oss-security/2026/10/21/28

Configurations

No configuration.

History

30 Oct 2026, 16:18

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 9.1

22 Oct 2026, 01:16

Type	Values Removed	Values Added
References		() http://www.openwall.com/lists/oss-security/2026/10/21/28 -

21 Oct 2026, 22:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-21 22:16

Updated : 2026-10-30 16:18

NVD link : CVE-2026-94140

Mitre link : CVE-2026-94140

CVE.ORG link : CVE-2026-94140

JSON object : View

Products Affected

No product.

CWE

CWE-322

Key Exchange without Entity Authentication

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