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Vulnerability record · CVE-2017-3204 · published 4 April 2017

CVE-2017-3204: Golang crypto vulnerability

Golang · Crypto

The Go SSH library (x/crypto/ssh) by default does not verify host keys, facilitating man-in-the-middle attacks. Default behavior changed in commit e4e2799 to require explicitly registering a hostkey verification mechanism.

8.1 CVSS 3.1 High EPSS 3.2% · top 12.5% CWE-310 · CWE-310
8.1CVSS 3.1 base score, v2 6.8
3.2%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
10References
17 Jun 2026Last modified by NVD

Description

The Go SSH library (x/crypto/ssh) by default does not verify host keys, facilitating man-in-the-middle attacks. Default behavior changed in commit e4e2799 to require explicitly registering a hostkey verification mechanism.

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
http://www.securityfocus.com/bid/97481 Third Party AdvisoryVDB Entry
https://bridge.grumpy-troll.org/2017/04/golang-ssh-security/ Third Party Advisory
https://github.com/golang/crypto/commit/e4e2799dd7aab89f583e1d898300d96367750991 PatchThird Party Advisory
https://github.com/golang/go/issues/19767 Third Party Advisory
https://godoc.org/golang.org/x/crypto/ssh Vendor Advisory
http://www.securityfocus.com/bid/97481 Third Party AdvisoryVDB Entry
https://bridge.grumpy-troll.org/2017/04/golang-ssh-security/ Third Party Advisory
https://github.com/golang/crypto/commit/e4e2799dd7aab89f583e1d898300d96367750991 PatchThird Party Advisory
https://github.com/golang/go/issues/19767 Third Party Advisory
https://godoc.org/golang.org/x/crypto/ssh Vendor Advisory

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2017-3204), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.