CVE-2018-10896

Name: CVE-2018-10896
Creator: NVD / NIST
Published: 2018-08-01T17:29:00.393+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.1/10EPSS 0.35%

Last modified Jun 17, 2026

CVE-2018-10896 is a high-severity vulnerability rated 7.1/10 on the CVSS scale. 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.. EPSS estimates a 0.35% chance of exploitation in the next 30 days.

Description

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.

Metrics

CVSS 3.1

7.1/10

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

EPSS Probability

0.35%

27.3th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-321

Affected Software

Vendor	Product	Versions
Canonical	Cloud-Init	>= 0.6.2, < 18.4

References

https://bugs.launchpad.net/cloud-init/+bug/1781094Patch, Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=1574338Issue Tracking, Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2018-10896Issue Tracking, Patch, Third Party Advisory
https://bugs.launchpad.net/cloud-init/+bug/1781094Patch, Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=1574338Issue Tracking, Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2018-10896Issue Tracking, Patch, Third Party Advisory

Timeline

Published: Aug 1, 2018
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2018-10896?

How severe is CVE-2018-10896?

CVE-2018-10896 has a CVSS score of 7.1/10 (HIGH severity). The EPSS model estimates a 0.35% probability of exploitation in the next 30 days.

How do I fix CVE-2018-10896?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2018-10896?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST