CVE-2020-26301 is a critical-severity (CVSS 10) OS Command Injection vulnerability in ssh2. 1 public exploit reference exists, so weaponization risk is real. A fix is available for ssh2 — see the affected versions and patch details below.
OS Command Injection in ssh2
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2020-26301 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 385,987 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
ssh2npmDescription
ssh2 is client and server modules written in pure JavaScript for node.js. In ssh2 before version 1.4.0 there is a command injection vulnerability. The issue only exists on Windows. This issue may lead to remote code execution if a client of the library calls the vulnerable method with untrusted input. This is fixed in version 1.4.0.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | ssh2 | all versions | 1.4.0npm install ssh2@1.4.0 |
Affected Products
ssh2ssh2_projectResearch use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for ssh2, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update ssh2 to 1.4.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2020-26301 is resolved across your whole dependency graph.
Workarounds
Stop passing untrusted input into the interpreter or shell: call the affected binary with an argument array rather than a composed command string, reject anything outside a strict allowlist of expected values, and run the component under an account that cannot reach beyond the work it legitimately does.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
This issue affects ssh2 as shipped with all versions of Red Hat Openshift Container Storage and Red Hat Openshift Data Foundations. However, this flaw requires a Windows based attack, and therefore, the impact is adjusted accordingly to a moderate risk.
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat OpenShift Container Storage 4.8.0 on RHEL-8 | ocs4/cephcsi-rhel8:v4.8.5-1 | RHSA-2021:4845 |
Frequently Asked Questions
Is CVE-2020-26301 in your dependencies?
Find it across npm, including transitive dependencies.