CVE-2016-6210

Severity: medium (CVSS 5.9 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 88.9% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2017-02-13 · updated 2026-06-17
Weakness: CWE-200

Description

sshd in OpenSSH before 7.3, when SHA256 or SHA512 are used for user password hashing, uses BLOWFISH hashing on a static password when the username does not exist, which allows remote attackers to enumerate users by leveraging the timing difference between responses when a large password is provided.

Affected products

OpenSSH: through 7.2

References

http://seclists.org/fulldisclosure/2016/Jul/51
http://www.debian.org/security/2016/dsa-3626
http://www.securityfocus.com/bid/91812
http://www.securitytracker.com/id/1036319
https://access.redhat.com/errata/RHSA-2017:2029
https://access.redhat.com/errata/RHSA-2017:2563
https://cert-portal.siemens.com/productcert/pdf/ssa-412672.pdf
https://security.gentoo.org/glsa/201612-18
https://security.netapp.com/advisory/ntap-20190206-0001/
https://www.exploit-db.com/exploits/40113/
https://www.exploit-db.com/exploits/40136/
https://www.openssh.com/txt/release-7.3

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