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Fencer Intel
medium 5.9

CVE-2016-6210 json

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 u…

published 2017-02-13 9 y ago modified 2026-06-17 4 mo ago also EUVD-2016-7143

cvss
5.9
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
88.9%
EPSS 88.9% chance of exploitation in 30 days, percentile 99.7%
public exploits
3
Metasploit, Exploit-DB

Summary

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.

Patch / fix

  • openssh Debian 14, Debian 13, Debian 12 1:7.2p2-6

debian advisories DEBIAN-CVE-2016-6210

  • openssh Ubuntu 14.04 LTS 1:6.6p1-2ubuntu2.8
  • openssh Ubuntu 16.04 LTS 1:7.2p2-4ubuntu2.1

ubuntu advisories UBUNTU-CVE-2016-6210

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • openssh RHEL 6 5.3p1-123.el6_9
  • openssh-ldap RHEL 6 5.3p1-123.el6_9
  • openssh-server RHEL 6 5.3p1-123.el6_9
  • openssh-askpass RHEL 6 5.3p1-123.el6_9
  • openssh-clients RHEL 6 5.3p1-123.el6_9
  • pam_ssh_agent_auth RHEL 6 0.9.3-123.el6_9
  • openssh RHEL 7 7.4p1-11.el7
  • openssh-cavs RHEL 7 7.4p1-11.el7

red hat advisories RHSA-2017:2563RHSA-2017:2029

  • openssh-openssl1 SLES 11-SECURITY 6.6p1-15.1
  • openssh SLES 11 SP3-TERADATA, SLES 11 SP3-LTSS, SLE Point of Sale 11 SP3 +3 more 6.2p2-0.33.2
  • openssh-askpass-gnome SLES 11 SP3-TERADATA, SLES 11 SP3-LTSS, SLE Point of Sale 11 SP3 +3 more 6.2p2-0.33.5
  • openssh SLES for SAP 11 SP4, SLES 11 SP4 6.6p1-28.1
  • openssh-askpass-gnome SLES for SAP 11 SP4, SLES 11 SP4 6.6p1-28.2
  • openssh SLES for SAP 12 SP1, SLES for SAP 12, SLES 12-LTSS +2 more 6.6p1-52.1
  • openssh-askpass-gnome SLES for SAP 12 SP1, SLES for SAP 12, SLES 12-LTSS +2 more 6.6p1-52.1

suse advisories SUSE-SU-2016:2555-1SUSE-SU-2016:2388-1SUSE-SU-2016:2281-1SUSE-SU-2016:2280-1

  • openssh openSUSE Tumbleweed 7.2p2-3.1

opensuse advisories openSUSE-SU-2024:10174-1

  • openssh Alpine 3.2 6.8_p1-r7
  • openssh Alpine 3.4, Alpine 3.3 7.2_p2-r1

alpine advisories ALPINE-CVE-2016-6210

Alpine secdb © Alpine Linux, from https://secdb.alpinelinux.org via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2016-6210 updated cvss 5.3

openssh: User enumeration via covert timing channel

  • Red Hat Enterprise Linux 5 openssh
    affected: no fix planned “Will not fix”
  • Red Hat Enterprise Linux Client (v. 7) openssh 7.4p1-11.el7, openssh-keycat 7.4p1-11.el7, openssh-server 7.4p1-11.el7, openssh-askpass 7.4p1-11.el7, openssh-clients 7.4p1-11.el7 Red Hat Enterprise Linux Client Optional (v. 7) openssh-cavs 7.4p1-11.el7, openssh-ldap 7.4p1-11.el7, pam_ssh_agent_auth 0.10.3-1.11.el7, openssh-server-sysvinit 7.4p1-11.el7 Red Hat Enterprise Linux ComputeNode (v. 7) openssh 7.4p1-11.el7, openssh-keycat 7.4p1-11.el7, openssh-server 7.4p1-11.el7, openssh-clients 7.4p1-11.el7 Red Hat Enterprise Linux ComputeNode Optional (v. 7) openssh-cavs 7.4p1-11.el7, openssh-ldap 7.4p1-11.el7, openssh-askpass 7.4p1-11.el7, pam_ssh_agent_auth 0.10.3-1.11.el7, openssh-server-sysvinit 7.4p1-11.el7
    fixed: vendor fix RHSA-2017:2029
  • Red Hat Enterprise Linux Desktop (v. 6) openssh 5.3p1-123.el6_9, openssh-server 5.3p1-123.el6_9, openssh-askpass 5.3p1-123.el6_9, openssh-clients 5.3p1-123.el6_9 Red Hat Enterprise Linux Desktop Optional (v. 6) openssh-ldap 5.3p1-123.el6_9, pam_ssh_agent_auth 0.9.3-123.el6_9 Red Hat Enterprise Linux HPC Node (v. 6) openssh 5.3p1-123.el6_9, openssh-server 5.3p1-123.el6_9, openssh-clients 5.3p1-123.el6_9 Red Hat Enterprise Linux HPC Node Optional (v. 6) openssh-ldap 5.3p1-123.el6_9, openssh-askpass 5.3p1-123.el6_9, pam_ssh_agent_auth 0.9.3-123.el6_9 Red Hat Enterprise Linux Server (v. 6) openssh 5.3p1-123.el6_9, openssh-server 5.3p1-123.el6_9, openssh-askpass 5.3p1-123.el6_9, openssh-clients 5.3p1-123.el6_9
    fixed: vendor fix RHSA-2017:2563
  • Red Hat Enterprise Linux Server (v. 7) openssh 7.4p1-11.el7, openssh-keycat 7.4p1-11.el7, openssh-server 7.4p1-11.el7, openssh-askpass 7.4p1-11.el7, openssh-clients 7.4p1-11.el7
    fixed: vendor fix RHSA-2017:2029
  • Red Hat Enterprise Linux Server Optional (v. 6) openssh-ldap 5.3p1-123.el6_9, pam_ssh_agent_auth 0.9.3-123.el6_9
    fixed: vendor fix RHSA-2017:2563
  • Red Hat Enterprise Linux Server Optional (v. 7) openssh-cavs 7.4p1-11.el7, openssh-ldap 7.4p1-11.el7, pam_ssh_agent_auth 0.10.3-1.11.el7, openssh-server-sysvinit 7.4p1-11.el7
    fixed: vendor fix RHSA-2017:2029
  • Red Hat Enterprise Linux Workstation (v. 6) openssh 5.3p1-123.el6_9, openssh-server 5.3p1-123.el6_9, openssh-askpass 5.3p1-123.el6_9, openssh-clients 5.3p1-123.el6_9
    fixed: vendor fix RHSA-2017:2563
  • Red Hat Enterprise Linux Workstation (v. 7) openssh 7.4p1-11.el7, openssh-keycat 7.4p1-11.el7, openssh-server 7.4p1-11.el7, openssh-askpass 7.4p1-11.el7, openssh-clients 7.4p1-11.el7
    fixed: vendor fix RHSA-2017:2029
show 2 more
  • Red Hat Enterprise Linux Workstation Optional (v. 6) openssh-ldap 5.3p1-123.el6_9, pam_ssh_agent_auth 0.9.3-123.el6_9
    fixed: vendor fix RHSA-2017:2563
  • Red Hat Enterprise Linux Workstation Optional (v. 7) openssh-cavs 7.4p1-11.el7, openssh-ldap 7.4p1-11.el7, pam_ssh_agent_auth 0.10.3-1.11.el7, openssh-server-sysvinit 7.4p1-11.el7
    fixed: vendor fix RHSA-2017:2029

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

cisa ICSA-22-349-21 updated cvss 5.9

Siemens SCALANCE X-200RNA Switch Devices

  • Siemens SCALANCE X204RNA (HSR) (6GK5204-0BA00-2MB2) <V3.2.7 Siemens SCALANCE X204RNA (PRP) (6GK5204-0BA00-2KB2) <V3.2.7 Siemens SCALANCE X204RNA EEC (HSR) (6GK5204-0BS00-2NA3) <V3.2.7 Siemens SCALANCE X204RNA EEC (PRP) (6GK5204-0BS00-3LA3) <V3.2.7 Siemens SCALANCE X204RNA EEC (PRP/HSR) (6GK5204-0BS00-3PA3) <V3.2.7
    affected: fixed in V3.2.7, mitigation support.industry.siemens.com

Facts from CISA's republication of the vendor's own advisory (CSAF); the linked advisory is the authoritative source. CISA notification · csaf

Timeline

  1. First public exploit (EDB-40113)
  2. Published

CISA SSVC

Exploitation
Proof of concept is public
Automatable
no
Technical impact
partial
Assessed
5 mo ago

Exploit prediction

88.94% chance of exploitation in the next 30 days, higher than 99.7% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

CVSS scores

assigned by version score vector
CISA ADP 3.1 5.9 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
CNA 3.1 5.9 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
NVD 3.0 5.9 CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
NVD 2.0 4.3 AV:N/AC:M/Au:N/C:P/I:N/A:N

Classification

Weakness
  • CWE-200 Exposure of Sensitive Information to an Unauthorized Actor

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.