Kopia up to 0.22.x HTTP Server /api/v1/repo/exists exec.CommandContext sshArguments os command injection

Summaryinfo

A vulnerability classified as critical has been found in Kopia up to 0.22.x. This impacts the function exec.CommandContext of the file /api/v1/repo/exists of the component HTTP Server. The manipulation of the argument sshArguments leads to os command injection. This vulnerability is listed as CVE-2026-45695. The attack may be initiated remotely. There is no available exploit.

Detailsinfo

A vulnerability was found in Kopia up to 0.22.x and classified as critical. This issue affects the function exec.CommandContext of the file /api/v1/repo/exists of the component HTTP Server. The manipulation of the argument sshArguments with an unknown input leads to a os command injection vulnerability. Using CWE to declare the problem leads to CWE-78. The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

Kopia is a cross-platform backup tool for Windows, macOS, and Linux with fast incremental backups, client-side end-to-end encryption, compression, and data deduplication. Prior to 0.23.0, Kopia's HTTP server started with --without-password accepts unauthenticated requests to /api/v1/repo/exists and forwards attacker-supplied SFTP storage configuration to blob.NewStorage, where externalSSH: true and sshArguments containing -oProxyCommand=<cmd> can cause exec.CommandContext("ssh") to invoke the command through OpenSSH. This issue is fixed in version 0.23.0.

The advisory is shared at github.com. The identification of this vulnerability is CVE-2026-45695 since 05/13/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details are known, but no exploit is available. MITRE ATT&CK project uses the attack technique T1202 for this issue.

Upgrading to version 0.23.0 eliminates this vulnerability.

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Productinfo

Name

• Kopia

Version

• 0.1
• 0.2
• 0.3
• 0.4
• 0.5
• 0.6
• 0.7
• 0.8
• 0.9
• 0.10
• 0.11
• 0.12
• 0.13
• 0.14
• 0.15
• 0.16
• 0.17
• 0.18
• 0.19
• 0.20
• 0.21
• 0.22

Website

• Product: https://github.com/kopia/kopia/

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Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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