---
title: "CVE-2026-45695: Kopia: RCE via SSH ProxyCommand Injection"
url: https://erroneo.us/security/cve/CVE-2026-45695/
description: "CVE-2026-45695 (github.com/kopia/kopia (Go)): Kopia is a cross-platform backup tool for Windows, macOS, and Linux with fast incremental backups, client-side…"
type: vulnerability-record
section: "Security Digest"
date_published: 2026-07-16
date_modified: 2026-07-16
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2026-45695"
kev: false
cvss: 9.8
epss: 0.0161
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2026-45695: Kopia: RCE via SSH ProxyCommand Injection

**Signal:** Critical and remotely reachable. No known exploitation yet, but it is network-reachable without credentials. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
- EPSS 1.6% , percentile 76: FIRST’s model estimates a 1.6% chance of exploitation activity in the next 30 days, higher than 76% of all scored CVEs (moderate). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Only applies if your dependency tree includes github.com/kopia/kopia (Go) <= 0.22.3, fixed in 0.23.0 . Check your lockfile, including transitive dependencies.

## What it 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= can cause exec.CommandContext("ssh") to invoke the command through OpenSSH. This issue is fixed in version 0.23.0.

## Affected packages

- Go `github.com/kopia/kopia` <= 0.22.3 → fixed: 0.23.0

## Affected products (CVE record)

- kopia kopia: < 0.23.0

## Severity

- GitHub_M CVSS 3.1: 9.8 `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`
- GitHub CVSS 3.1: 9.8 `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`

## Exploitation

- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation none , automatable yes , technical impact total .
- FIRST EPSS (model of 2026-10-21): 1.61% probability of exploitation activity in the next 30 days; percentile 76.

## Sources

- [GitHub Advisory GHSA-2q4c-3mrw-63c3](https://github.com/advisories/GHSA-2q4c-3mrw-63c3)
- [CVE.org record CVE-2026-45695](https://www.cve.org/CVERecord?id=CVE-2026-45695)
- [NVD entry CVE-2026-45695](https://nvd.nist.gov/vuln/detail/CVE-2026-45695)
- [github.com](https://github.com/kopia/kopia/security/advisories/GHSA-2q4c-3mrw-63c3)
- [github.com](https://github.com/kopia/kopia/pull/5354)
- [github.com](https://github.com/kopia/kopia/commit/c26c6a1b9734c5089217986ffa5cd19f8a6b8900)
- [github.com](https://github.com/kopia/kopia/releases/tag/v0.23.0)

---
Source page: https://erroneo.us/security/cve/CVE-2026-45695/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt