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.'
The MITRE CVE dictionary describes this issue as:
Find out more about CVE-2018-15919 from the MITRE CVE dictionary dictionary and NIST NVD.
NOTE: The following CVSS v3 metrics and score provided are preliminary and subject to review.
| CVSS3 Base Score | 5.3 |
|---|---|
| CVSS3 Base Metrics | CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N |
| Attack Vector | Network |
| Attack Complexity | Low |
| Privileges Required | None |
| User Interaction | None |
| Scope | Unchanged |
| Confidentiality | Low |
| Integrity Impact | None |
| Availability Impact | None |
| Platform | Package | State |
|---|---|---|
| Red Hat Virtualization 4 | openssh | Will not fix |
| Red Hat OpenShift Enterprise 3 | openssh | Will not fix |
| Red Hat Enterprise Linux 7 | openssh | Affected |
| Red Hat Enterprise Linux 6 | openssh | Not affected |
| Red Hat Enterprise Linux 5 | openssh | Not affected |
Vulmon