How severe is CVE-2018-15919?

CVE-2018-15919 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2018-15919 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (88th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-15919?

CVE-2018-15919 primarily affects Openbsd Openssh. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-15919?

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

When was CVE-2018-15919 published?

CVE-2018-15919 was published on 2018-08-28 and last updated on 2026-06-17.

CVE-2018-15919

CVE-2018-15919 is a medium-severity vulnerability in Openbsd Openssh with a CVSS 3.x base score of 5.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-200.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v2: 5.0
EPSS exploit prediction: 4% (88th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-200
Affected product: Openbsd Openssh
Published: 2018-08-28
Last modified: 2026-06-17

Description

Remotely observable behaviour in auth-gss2.c in OpenSSH through 7.8 could be used by remote attackers to detect existence of users on a target system when GSS2 is in use. NOTE: the discoverer states 'We understand that the OpenSSH developers do not want to treat such a username enumeration (or "oracle") as a vulnerability.'

Frequently asked questions

What is CVE-2018-15919?: Remotely observable behaviour in auth-gss2.c in OpenSSH through 7.8 could be used by remote attackers to detect existence of users on a target system when GSS2 is in use. NOTE: the discoverer states 'We understand that the OpenSSH developers do not want to treat such a username enumeration (or "oracle") as a vulnerability.'
How severe is CVE-2018-15919?: CVE-2018-15919 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2018-15919 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (88th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-15919?: CVE-2018-15919 primarily affects Openbsd Openssh. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-15919?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2018-15919 published?: CVE-2018-15919 was published on 2018-08-28 and last updated on 2026-06-17.

References

Affected products (6)

cpe:2.3:a:openbsd:openssh:*:*:*:*:*:*:*:*
cpe:2.3:a:netapp:cloud_backup:-:*:*:*:*:*:*:*
cpe:2.3:a:netapp:data_ontap_edge:-:*:*:*:*:*:*:*
cpe:2.3:a:netapp:ontap_select_deploy:-:*:*:*:*:*:*:*
cpe:2.3:a:netapp:steelstore:-:*:*:*:*:*:*:*
cpe:2.3:o:netapp:cn1610_firmware:-:*:*:*:*:*:*:*

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Threat intelligence

Threat-intel indicators referencing this CVE:

14.18.122.98 (ipv4-addr)
124.223.78.215 (ipv4-addr)
120.48.123.76 (ipv4-addr)
60.12.249.51 (ipv4-addr)
113.0.152.164 (ipv4-addr)
45.84.120.3 (ipv4-addr)
81.192.46.36 (ipv4-addr)
76.79.213.69 (ipv4-addr)