Vulnerability Name:

CVE-2018-10896 (CCN-147923)

Assigned:2018-07-06
Published:2018-07-06
Updated:2023-02-13
Summary: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.
CVSS v3 Severity:7.1 High (CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N)
6.3 Medium (Temporal CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N/E:U/RL:U/RC:R)
Exploitability Metrics:Attack Vector (AV): Local
Attack Complexity (AC): Low
Privileges Required (PR): Low
User Interaction (UI): None
Scope:Scope (S): Unchanged
Impact Metrics:Confidentiality (C): High
Integrity (I): High
Availibility (A): None
4.6 Medium (CCN CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N)
4.1 Medium (CCN Temporal CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N/E:U/RL:U/RC:R)
Exploitability Metrics:Attack Vector (AV): Local
Attack Complexity (AC): Low
Privileges Required (PR): Low
User Interaction (UI): Required
Scope:Scope (S): Changed
Impact Metrics:Confidentiality (C): Low
Integrity (I): Low
Availibility (A): None
4.6 Medium (REDHAT CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N)
4.1 Medium (REDHAT Temporal CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N/E:U/RL:U/RC:R)
Exploitability Metrics:Attack Vector (AV): Local
Attack Complexity (AC): Low
Privileges Required (PR): Low
User Interaction (UI): Required
Scope:Scope (S): Changed
Impact Metrics:Confidentiality (C): Low
Integrity (I): Low
Availibility (A): None
CVSS v2 Severity:3.6 Low (CVSS v2 Vector: AV:L/AC:L/Au:N/C:P/I:P/A:N)
Exploitability Metrics:Access Vector (AV): Local
Access Complexity (AC): Low
Authentication (Au): None
Impact Metrics:Confidentiality (C): Partial
Integrity (I): Partial
Availibility (A): None
3.2 Low (CCN CVSS v2 Vector: AV:L/AC:L/Au:S/C:P/I:P/A:N)
Exploitability Metrics:Access Vector (AV): Local
Access Complexity (AC): Low
Athentication (Au): Single_Instance
Impact Metrics:Confidentiality (C): Partial
Integrity (I): Partial
Availibility (A): None
Vulnerability Type:CWE-321
Vulnerability Consequences:Gain Access
References:Source: MITRE
Type: CNA
CVE-2018-10896

Source: secalert@redhat.com
Type: Patch, Third Party Advisory
secalert@redhat.com

Source: CCN
Type: Red Hat Bugzilla – Bug 1574338
CVE-2018-10896 cloud-init: SSH host keys are not regenerated for the new instances

Source: secalert@redhat.com
Type: Issue Tracking, Third Party Advisory
secalert@redhat.com

Source: secalert@redhat.com
Type: Issue Tracking, Patch, Third Party Advisory
secalert@redhat.com

Source: CCN
Type: cloud-init Web site
The standard for customising cloud instances

Source: XF
Type: UNKNOWN
cloudinit-cve201810896-weak-security(147923)

Vulnerable Configuration:Configuration RedHat 1:
  • cpe:/a:redhat:enterprise_linux:8:*:*:*:*:*:*:*
    • Configuration RedHat 2:
  • cpe:/a:redhat:enterprise_linux:8::appstream:*:*:*:*:*
    • Configuration RedHat 3:
  • cpe:/o:redhat:enterprise_linux:7:*:*:*:*:*:*:*
    • Configuration RedHat 4:
  • cpe:/o:redhat:enterprise_linux:7::server:*:*:*:*:*

    • * Denotes that component is vulnerable
    Oval Definitions
    Definition IDClassTitleLast Modified
    oval:com.redhat.rhsa:def:20203898
    P
    		RHSA-2020:3898: cloud-init security, bug fix, and enhancement update (Moderate)
    2020-09-29
    oval:com.redhat.rhsa:def:20203050
    P
    		RHSA-2020:3050: cloud-init security, bug fix, and enhancement update (Low)
    2020-07-21
    BACK