How severe is CVE-2016-6210?

CVE-2016-6210 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2016-6210 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 89% (100th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2016-6210?

CVE-2016-6210 affects Openbsd Openssh. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2016-6210?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2016-6210 published?

CVE-2016-6210 was published on 2017-02-13 and last updated on 2026-06-17.

CVE-2016-6210

CVE-2016-6210 is a medium-severity vulnerability in Openbsd Openssh with a CVSS 3.x base score of 5.9. Its EPSS exploit-prediction score of 89% places it in the 100th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-200.

Key facts

Severity: Medium (CVSS 3.x base score 5.9)
CVSS v2: 4.3
EPSS exploit prediction: 89% (100th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-200
Affected product: Openbsd Openssh
Published: 2017-02-13
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2016-6210?: 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.
How severe is CVE-2016-6210?: CVE-2016-6210 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2016-6210 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 89% (100th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2016-6210?: CVE-2016-6210 affects Openbsd Openssh. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2016-6210?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2016-6210 published?: CVE-2016-6210 was published on 2017-02-13 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:openbsd:openssh:*:p2:*:*:*:*:*:*

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Threat intelligence

Threat-intel indicators referencing this CVE:

60.166.8.174 (ipv4-addr)
60.166.31.198 (ipv4-addr)
183.66.149.42 (ipv4-addr)
151.237.115.208 (ipv4-addr)
41.219.149.74 (ipv4-addr)
175.203.199.118 (ipv4-addr)
218.146.45.68 (ipv4-addr)
67.197.111.225 (ipv4-addr)