CVE-2020-8903
CVSS V2 Medium 6.9
CVSS V3 High 7.8
Description
A vulnerability in Google Cloud Platform's guest-oslogin versions between 20190304 and 20200507 allows a user that is only granted the role "roles/compute.osLogin" to escalate privileges to root. Using their membership to the "adm" group, users with this role are able to read the DHCP XID from the systemd journal. Using the DHCP XID, it is then possible to set the IP address and hostname of the instance to any value, which is then stored in /etc/hosts. An attacker can then point metadata.google.internal to an arbitrary IP address and impersonate the GCE metadata server which make it is possible to instruct the OS Login PAM module to grant administrative privileges. All images created after 2020-May-07 (20200507) are fixed, and if you cannot update, we recommend you edit /etc/group/security.conf and remove the "adm" user from the OS Login entry.
Overview
- CVE ID
- CVE-2020-8903
- Assigner
- cve-coordination@google.com
- Vulnerability Status
- Analyzed
- Published Version
- 2020-06-22T14:15:11
- Last Modified Date
- 2022-09-30T23:06:51
Weakness Enumerations
CPE Configuration (Product)
| CPE | Vulnerable | Operator | Version Start | Version End |
|---|---|---|---|---|
| cpe:2.3:a:google:guest-oslogin:*:*:*:*:*:*:*:* | 1 | OR | 20190304.00 | 20200507.00 |
| cpe:2.3:o:opensuse:leap:15.1:*:*:*:*:*:*:* | 1 | OR | ||
| cpe:2.3:o:opensuse:leap:15.2:*:*:*:*:*:*:* | 1 | OR |
CVSS Version 2
- Version
- 2.0
- Vector String
- AV:L/AC:M/Au:N/C:C/I:C/A:C
- Access Vector
- LOCAL
- Access Compatibility
- MEDIUM
- Authentication
- NONE
- Confidentiality Impact
- COMPLETE
- Integrity Impact
- COMPLETE
- Availability Impact
- COMPLETE
- Base Score
- 6.9
- Severity
- MEDIUM
- Exploitability Score
- 3.4
- Impact Score
- 10
CVSS Version 3
- Version
- 3.1
- Vector String
- CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- Attack Vector
- LOCAL
- Attack Compatibility
- LOW
- Privileges Required
- LOW
- User Interaction
- NONE
- Scope
- UNCHANGED
- Confidentiality Impact
- HIGH
- Availability Impact
- HIGH
- Base Score
- 7.8
- Base Severity
- HIGH
- Exploitability Score
- 1.8
- Impact Score
- 5.9
References
| Reference URL | Reference Tags |
|---|---|
| https://github.com/GoogleCloudPlatform/guest-oslogin/pull/29 | Patch Third Party Advisory |
| https://cloud.google.com/support/bulletins/#gcp-2020-008 | Vendor Advisory |
| https://gitlab.com/gitlab-com/gl-security/gl-redteam/red-team-tech-notes/-/tree/master/oslogin-privesc-june-2020 | Exploit Third Party Advisory |
| http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00037.html | |
| http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00047.html |
Sources
| Source Name | Source URL |
|---|---|
| NIST | https://nvd.nist.gov/vuln/detail/CVE-2020-8903 |
| MITRE | https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-8903 |
History
| Created | Old Value | New Value | Data Type | Notes |
|---|---|---|---|---|
| 2022-05-10 16:40:32 | Added to TrackCVE | |||
| 2022-12-04 18:34:08 | security@google.com | cve-coordination@google.com | CVE Assigner | updated |
| 2022-12-04 18:34:08 | 2020-06-22T14:15Z | 2020-06-22T14:15:11 | CVE Published Date | updated |
| 2022-12-04 18:34:08 | 2022-09-30T23:06:51 | CVE Modified Date | updated | |
| 2022-12-04 18:34:08 | Analyzed | Vulnerability Status | updated |