Vulnerability Details : CVE-2018-10896
The default cloud-init configuration, in cloud-init 0.6.2 and newer, included "ssh_deletekeys: 0", disabling cloud-init's deletion of ssh host keys. In some environments, this could lead to instances created by cloning a golden master or template system, sharing ssh host keys, and being able to impersonate one another or conduct man-in-the-middle attacks.
Exploit prediction scoring system (EPSS) score for CVE-2018-10896
Probability of exploitation activity in the next 30 days: 0.05%
Percentile, the proportion of vulnerabilities that are scored at or less: ~ 18 % EPSS Score History EPSS FAQ
CVSS scores for CVE-2018-10896
| Base Score | Base Severity | CVSS Vector | Exploitability Score | Impact Score | Score Source |
|---|---|---|---|---|---|
|
3.6
|
LOW | AV:L/AC:L/Au:N/C:P/I:P/A:N |
3.9
|
4.9
|
NIST |
|
4.6
|
MEDIUM | CVSS:3.0/AV:L/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N |
1.5
|
2.7
|
Red Hat, Inc. |
|
7.1
|
HIGH | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N |
1.8
|
5.2
|
NIST |
CWE ids for CVE-2018-10896
-
The use of a hard-coded cryptographic key significantly increases the possibility that encrypted data may be recovered.Assigned by: secalert@redhat.com (Primary)
References for CVE-2018-10896
-
https://bugzilla.redhat.com/show_bug.cgi?id=1574338
1574338 – CVE-2018-10896 cloud-init: SSH host keys are not regenerated for the new instances [rhel-7]Issue Tracking;Third Party Advisory
-
https://bugs.launchpad.net/cloud-init/+bug/1781094
Bug #1781094 “cloud.cfg.tmpl should not include “ssh_deletekeys:...” : Bugs : cloud-initPatch;Third Party Advisory
-
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2018-10896
1598831 – (CVE-2018-10896) CVE-2018-10896 cloud-init: default configuration disabled deletion of SSH host keysIssue Tracking;Patch;Third Party Advisory
Products affected by CVE-2018-10896
- cpe:2.3:a:canonical:cloud-init:*:*:*:*:*:*:*:*