CVE-2020-26301: ssh2 is client and server modules written in pure JavaScript for node.js

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HIGH 7.5REMOTEUPGRADE

CVE-2020-26301 is a high-severity flaw (CVSS 7.5) affecting ssh2. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

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.

Why this priority

High severity
EPSS top 10%: very likely to be exploited
Public exploit reference
Remotely exploitable, no login, no user action

A fixed release or distro patch exists.

Risk facts

CVSS score	7.5 (High)
Attack vector	Network (remote)
Attack complexity	High
Privileges needed	None
User interaction	None
EPSS exploit chance	3.8% (top 10%)
CISA exploited list	No
Weakness	CWE-78
Published	2021-09-20
Last modified	2026-06-17

Publisher (CNA): GitHub, Inc. · Vendor: ssh2 project

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2021-09-20 20:15 UTCPublished CVE record published
2026-06-17 03:08 UTCUpdated Record last modified

ssh2 project ssh2 UPGRADE

Affected: < 1.4.0

Fixed in: 1.4.0

Safe to downgrade to: no unaffected older release

1. Check installed version

npm ls ssh2

2. UPGRADE to 1.4.0

npm install ssh2@">=1.4.0"

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2020-26301?

ssh2: upgrade to 1.4.0. Exact commands for each OS are on this page.

Is CVE-2020-26301 being exploited?

CVE-2020-26301 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2020-26301 affect?

CVE-2020-26301 affects ssh2. Severity is high (CVSS 7.5). 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

How urgent is CVE-2020-26301?

Priority 59/100. High severity; EPSS top 10%: very likely to be exploited; Public exploit reference; Remotely exploitable, no login, no user action

Software pages

Node.js vulnerabilities · Windows vulnerabilities

Related CVEs

CVE-2025-70034 HIGH 7.5 DOWNGRADE An issue pertaining to CWE-1333: Inefficient Regular Expression Complexity (4.19) was discovered in mscdex ssh

References

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