CVE-2026-45695 Kopia: Unauthenticated RCE via SSH ProxyCommand Injection when --insecure --without-password is used
Unauthenticated attackers can execute arbitrary commands via SSH ProxyCommand injection when Kopia's HTTP server is configured with --insecure and --without-password.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-45695?
CVE-2026-45695 is a critical command injection vulnerability in kopia, published on 16 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
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.
Which versions are affected by CVE-2026-45695?
3 open source packages ship an affected version, including github.com/kopia/kopia.
| Package | Affected | Fixed in |
|---|---|---|
github.com/kopia/kopia Go | All versions | 0.23.0 |
github.com/kopia/kopia Go | All versions | 0.23.0 |
github.com/kopia/kopia Go | All versions | 0.23.0 |
How do I fix CVE-2026-45695?
Upgrade github.com/kopia/kopia to 0.23.0 or later.
Upgrade, and pass arguments to programs as a list instead of through a shell. More about Command injection.
Is CVE-2026-45695 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-45695 exists.
Public exploit code: 1 Nuclei template.
Sources
Also known as GHSA-2q4c-3mrw-63c3, GO-2026-5009.