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 tar…

Published 8 y ago 2018-08-28 · modified 4 mo ago 2026-06-17 · JSON

CVSS

5.3

v3.1 · CNA

CISA KEV

not known exploited

EPSS

3.5%

percentile 89%

Public exploits

none known

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.'

CISA SSVC assessment

Exploitation: Proof of concept public
Automatable: yes
Technical impact: partial
Assessed: 10 mo ago 2025-12-18

Exploit prediction (EPSS)

3.51% probability of exploitation in the next 30 days, higher than 89% of all scored CVEs.

CVSS scores

Assigned by	Version	Score	Vector
CISA ADP	3.1	5.3	`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N`
CNA	3.1	5.3	`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N`
NVD	3.0	5.3	`CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N`
NVD	2.0	5.0	`AV:N/AC:L/Au:N/C:P/I:N/A:N`

Classification

Weakness

CWE-200 Exposure of Sensitive Information to an Unauthorized Actor

References

security.netapp.com /advisory/ntap-20181221-0001/ · x_refsource_CONFIRM, x_transferred
securityfocus.com /bid/105163 · vdb-entry, x_refsource_BID, x_transferred
seclists.org /oss-sec/2018/q3/180 · x_refsource_MISC, x_transferred

Sources

CVE List: CVE-2018-15919
NVD: CVE-2018-15919

vulnwire keeps one entry per vulnerability: the CVE id wins, then GHSA; records that alias each other are merged. Machine-readable: JSON.