by Kastro
Paper/Archive/CVE-2026-45695

CVE-2026-45695

kopia kopia — Kopia: Unauthenticated RCE via SSH ProxyCommand Injection when --insecure --without-password is used

EPSS 2%CVSS 9.8
critical.is priorityof 100
45
CVSS 9.8 (CNA)9.8 / 10 × 3029.4Not in CISA KEV+300.0EPSS percentile 75.9.759 × 2015.2No public exploit+100.0SSVC exploitation: none+100.0
Description · from the CVE record

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.

Affected

ProductAffectedFixed inSource
kopia< 0.23.0–CNA

Scores by source

GitHub_M (CNA)9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CISA ADPSSVCExploitation: none · Automatable: yes · Technical impact: total

References

refgithub.com/kopia/kopia/security/advisories/GHSA-2q4c-3mrw-63c3refgithub.com/kopia/kopia/pull/5354refgithub.com/kopia/kopia/commit/c26c6a1b9734c5089217986ffa5cd19f8a6b8900refgithub.com/kopia/kopia/releases/tag/v0.23.0