High severity · published Apr 4, 2017
CVE-2017-3204
The Go SSH library (x/crypto/ssh) by default does not verify host keys, facilitating man-in-the-middle attacks
8.1
CVSS
3.2%
EPSS
No
On KEV
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 vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)3.2% · higher than 88% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CR
Crypto · Golang
through 2017-03-17 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2017-3204
CVE.org
https://www.cve.org/CVERecord?id=CVE-2017-3204
Third Party Advisory
http://www.securityfocus.com/bid/97481
Third Party Advisory
https://bridge.grumpy-troll.org/2017/04/golang-ssh-security/
Patch
https://github.com/golang/crypto/commit/e4e2799dd7aab89f583e1d898300d96367750991
Third Party Advisory
https://github.com/golang/go/issues/19767
Vendor Advisory
https://godoc.org/golang.org/x/crypto/ssh
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