UBUNTU-CVE-2018-20217

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Source
https://ubuntu.com/security/CVE-2018-20217
Import Source
https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2018/UBUNTU-CVE-2018-20217.json
JSON Data
https://api.test.osv.dev/v1/vulns/UBUNTU-CVE-2018-20217
Upstream
Downstream
Related
Published
2018-12-26T21:29:00Z
Modified
2025-09-08T16:45:06Z
Severity
  • 5.3 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H CVSS Calculator
  • 5.3 (Medium) CVSS_V3 - CVSS:3.0/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H CVSS Calculator
  • Ubuntu - medium
Summary
[none]
Details

A Reachable Assertion issue was discovered in the KDC in MIT Kerberos 5 (aka krb5) before 1.17. If an attacker can obtain a krbtgt ticket using an older encryption type (single-DES, triple-DES, or RC4), the attacker can crash the KDC by making an S4U2Self request.

References

Affected packages

Ubuntu:Pro:14.04:LTS / krb5

Package

Name
krb5
Purl
pkg:deb/ubuntu/krb5@1.12+dfsg-2ubuntu5.4+esm1?arch=source&distro=trusty/esm

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
1.12+dfsg-2ubuntu5.4+esm1

Affected versions

1.*

1.10.1+dfsg-6.1ubuntu1
1.11.3+dfsg-3ubuntu2
1.12+dfsg-2ubuntu1
1.12+dfsg-2ubuntu2
1.12+dfsg-2ubuntu3
1.12+dfsg-2ubuntu4
1.12+dfsg-2ubuntu4.2
1.12+dfsg-2ubuntu5
1.12+dfsg-2ubuntu5.1
1.12+dfsg-2ubuntu5.2
1.12+dfsg-2ubuntu5.3
1.12+dfsg-2ubuntu5.4

Ecosystem specific 

{
    "availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro",
    "binaries": [
        {
            "binary_name": "krb5-admin-server",
            "binary_version": "1.12+dfsg-2ubuntu5.4+esm1"
        },
        {
            "binary_name": "krb5-gss-samples",
            "binary_version": "1.12+dfsg-2ubuntu5.4+esm1"
        },
        {
            "binary_name": "krb5-kdc",
            "binary_version": "1.12+dfsg-2ubuntu5.4+esm1"
        },
        {
            "binary_name": "krb5-kdc-ldap",
            "binary_version": "1.12+dfsg-2ubuntu5.4+esm1"
        },
        {
            "binary_name": "krb5-locales",
            "binary_version": "1.12+dfsg-2ubuntu5.4+esm1"
        },
        {
            "binary_name": "krb5-multidev",
            "binary_version": "1.12+dfsg-2ubuntu5.4+esm1"
        },
        {
            "binary_name": "krb5-otp",
            "binary_version": "1.12+dfsg-2ubuntu5.4+esm1"
        },
        {
            "binary_name": "krb5-pkinit",
            "binary_version": "1.12+dfsg-2ubuntu5.4+esm1"
        },
        {
            "binary_name": "krb5-user",
            "binary_version": "1.12+dfsg-2ubuntu5.4+esm1"
        },
        {
            "binary_name": "libgssapi-krb5-2",
            "binary_version": "1.12+dfsg-2ubuntu5.4+esm1"
        },
        {
            "binary_name": "libgssrpc4",
            "binary_version": "1.12+dfsg-2ubuntu5.4+esm1"
        },
        {
            "binary_name": "libk5crypto3",
            "binary_version": "1.12+dfsg-2ubuntu5.4+esm1"
        },
        {
            "binary_name": "libkadm5clnt-mit9",
            "binary_version": "1.12+dfsg-2ubuntu5.4+esm1"
        },
        {
            "binary_name": "libkadm5srv-mit8",
            "binary_version": "1.12+dfsg-2ubuntu5.4+esm1"
        },
        {
            "binary_name": "libkadm5srv-mit9",
            "binary_version": "1.12+dfsg-2ubuntu5.4+esm1"
        },
        {
            "binary_name": "libkdb5-7",
            "binary_version": "1.12+dfsg-2ubuntu5.4+esm1"
        },
        {
            "binary_name": "libkrad-dev",
            "binary_version": "1.12+dfsg-2ubuntu5.4+esm1"
        },
        {
            "binary_name": "libkrad0",
            "binary_version": "1.12+dfsg-2ubuntu5.4+esm1"
        },
        {
            "binary_name": "libkrb5-3",
            "binary_version": "1.12+dfsg-2ubuntu5.4+esm1"
        },
        {
            "binary_name": "libkrb5-dev",
            "binary_version": "1.12+dfsg-2ubuntu5.4+esm1"
        },
        {
            "binary_name": "libkrb5support0",
            "binary_version": "1.12+dfsg-2ubuntu5.4+esm1"
        }
    ]
}

Ubuntu:Pro:16.04:LTS / krb5

Package

Name
krb5
Purl
pkg:deb/ubuntu/krb5@1.13.2+dfsg-5ubuntu2.2+esm3?arch=source&distro=esm-infra/xenial

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
1.13.2+dfsg-5ubuntu2.2+esm3

Affected versions

1.*

1.13.2+dfsg-2
1.13.2+dfsg-3
1.13.2+dfsg-4
1.13.2+dfsg-5
1.13.2+dfsg-5ubuntu1
1.13.2+dfsg-5ubuntu2
1.13.2+dfsg-5ubuntu2.1
1.13.2+dfsg-5ubuntu2.1+esm1
1.13.2+dfsg-5ubuntu2.2

Ecosystem specific 

{
    "availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro",
    "binaries": [
        {
            "binary_name": "krb5-admin-server",
            "binary_version": "1.13.2+dfsg-5ubuntu2.2+esm3"
        },
        {
            "binary_name": "krb5-gss-samples",
            "binary_version": "1.13.2+dfsg-5ubuntu2.2+esm3"
        },
        {
            "binary_name": "krb5-k5tls",
            "binary_version": "1.13.2+dfsg-5ubuntu2.2+esm3"
        },
        {
            "binary_name": "krb5-kdc",
            "binary_version": "1.13.2+dfsg-5ubuntu2.2+esm3"
        },
        {
            "binary_name": "krb5-kdc-ldap",
            "binary_version": "1.13.2+dfsg-5ubuntu2.2+esm3"
        },
        {
            "binary_name": "krb5-locales",
            "binary_version": "1.13.2+dfsg-5ubuntu2.2+esm3"
        },
        {
            "binary_name": "krb5-multidev",
            "binary_version": "1.13.2+dfsg-5ubuntu2.2+esm3"
        },
        {
            "binary_name": "krb5-otp",
            "binary_version": "1.13.2+dfsg-5ubuntu2.2+esm3"
        },
        {
            "binary_name": "krb5-pkinit",
            "binary_version": "1.13.2+dfsg-5ubuntu2.2+esm3"
        },
        {
            "binary_name": "krb5-user",
            "binary_version": "1.13.2+dfsg-5ubuntu2.2+esm3"
        },
        {
            "binary_name": "libgssapi-krb5-2",
            "binary_version": "1.13.2+dfsg-5ubuntu2.2+esm3"
        },
        {
            "binary_name": "libgssrpc4",
            "binary_version": "1.13.2+dfsg-5ubuntu2.2+esm3"
        },
        {
            "binary_name": "libk5crypto3",
            "binary_version": "1.13.2+dfsg-5ubuntu2.2+esm3"
        },
        {
            "binary_name": "libkadm5clnt-mit9",
            "binary_version": "1.13.2+dfsg-5ubuntu2.2+esm3"
        },
        {
            "binary_name": "libkadm5srv-mit9",
            "binary_version": "1.13.2+dfsg-5ubuntu2.2+esm3"
        },
        {
            "binary_name": "libkdb5-8",
            "binary_version": "1.13.2+dfsg-5ubuntu2.2+esm3"
        },
        {
            "binary_name": "libkrad-dev",
            "binary_version": "1.13.2+dfsg-5ubuntu2.2+esm3"
        },
        {
            "binary_name": "libkrad0",
            "binary_version": "1.13.2+dfsg-5ubuntu2.2+esm3"
        },
        {
            "binary_name": "libkrb5-3",
            "binary_version": "1.13.2+dfsg-5ubuntu2.2+esm3"
        },
        {
            "binary_name": "libkrb5-dev",
            "binary_version": "1.13.2+dfsg-5ubuntu2.2+esm3"
        },
        {
            "binary_name": "libkrb5support0",
            "binary_version": "1.13.2+dfsg-5ubuntu2.2+esm3"
        }
    ]
}

Ubuntu:18.04:LTS / krb5

Package

Name
krb5
Purl
pkg:deb/ubuntu/krb5@1.16-2ubuntu0.3?arch=source&distro=bionic

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
1.16-2ubuntu0.3

Affected versions

1.*

1.15.1-2
1.16-2
1.16-2build1
1.16-2ubuntu0.1
1.16-2ubuntu0.2

Ecosystem specific 

{
    "availability": "No subscription required",
    "binaries": [
        {
            "binary_name": "krb5-admin-server",
            "binary_version": "1.16-2ubuntu0.3"
        },
        {
            "binary_name": "krb5-gss-samples",
            "binary_version": "1.16-2ubuntu0.3"
        },
        {
            "binary_name": "krb5-k5tls",
            "binary_version": "1.16-2ubuntu0.3"
        },
        {
            "binary_name": "krb5-kdc",
            "binary_version": "1.16-2ubuntu0.3"
        },
        {
            "binary_name": "krb5-kdc-ldap",
            "binary_version": "1.16-2ubuntu0.3"
        },
        {
            "binary_name": "krb5-kpropd",
            "binary_version": "1.16-2ubuntu0.3"
        },
        {
            "binary_name": "krb5-locales",
            "binary_version": "1.16-2ubuntu0.3"
        },
        {
            "binary_name": "krb5-multidev",
            "binary_version": "1.16-2ubuntu0.3"
        },
        {
            "binary_name": "krb5-otp",
            "binary_version": "1.16-2ubuntu0.3"
        },
        {
            "binary_name": "krb5-pkinit",
            "binary_version": "1.16-2ubuntu0.3"
        },
        {
            "binary_name": "krb5-user",
            "binary_version": "1.16-2ubuntu0.3"
        },
        {
            "binary_name": "libgssapi-krb5-2",
            "binary_version": "1.16-2ubuntu0.3"
        },
        {
            "binary_name": "libgssrpc4",
            "binary_version": "1.16-2ubuntu0.3"
        },
        {
            "binary_name": "libk5crypto3",
            "binary_version": "1.16-2ubuntu0.3"
        },
        {
            "binary_name": "libkadm5clnt-mit11",
            "binary_version": "1.16-2ubuntu0.3"
        },
        {
            "binary_name": "libkadm5srv-mit11",
            "binary_version": "1.16-2ubuntu0.3"
        },
        {
            "binary_name": "libkdb5-9",
            "binary_version": "1.16-2ubuntu0.3"
        },
        {
            "binary_name": "libkrad-dev",
            "binary_version": "1.16-2ubuntu0.3"
        },
        {
            "binary_name": "libkrad0",
            "binary_version": "1.16-2ubuntu0.3"
        },
        {
            "binary_name": "libkrb5-3",
            "binary_version": "1.16-2ubuntu0.3"
        },
        {
            "binary_name": "libkrb5-dev",
            "binary_version": "1.16-2ubuntu0.3"
        },
        {
            "binary_name": "libkrb5support0",
            "binary_version": "1.16-2ubuntu0.3"
        }
    ]
}