Is there a public PoC exploit available for CVE-2020-8903?

Yes, a public proof-of-concept exploit is available for CVE-2020-8903. Prioritise patching immediately. EPSS: 0.3%.

Is there a patch available for CVE-2020-8903?

Yes, a patch is available for CVE-2020-8903. Update the affected software to the latest version immediately.

Guest Oslogin CVE-2020-8903

Q: What is the CVSS score of CVE-2020-8903?

CVE-2020-8903 has a CVSS 4.0 base score of 7.3 (High). CVSS vector: CVSS:4.0/AV:L/AC:H/AT:N/PR:L/UI:A/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X. EPSS exploitation probability: 0.3%.

HIGH

Incorrect Default Permissions (CWE-276)

2020-06-22 cve-coordination@google.com

Google Privilege Escalation Guest Oslogin Leap

7.3

CVSS 4.0 · Vendor: google

Severity by source

Vendor (google) PRIMARY

7.3 HIGH

CVSS:4.0/AV:L/AC:H/AT:N/PR:L/UI:A/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Primary rating from Vendor (google) · only source for this CVE.

CVSS VectorVendor: google

CVSS:4.0/AV:L/AC:H/AT:N/PR:L/UI:A/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Attack Vector

Local

Attack Complexity

High

Privileges Required

Low

User Interaction

Scope

Lifecycle Timeline

CVE Published

Jun 22, 2020 - 14:15 cve.org

HIGH 7.3

DescriptionCVE.org

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.

AnalysisAI

Technical ContextAI

This vulnerability is classified as Incorrect Default Permissions (CWE-276), which allows attackers to access resources due to overly permissive default settings. 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. Affected products include: Google Guest-Oslogin, Opensuse Leap.

RemediationAI

A vendor patch is available. Apply the latest security update as soon as possible. Set restrictive default permissions, follow principle of least privilege, review defaults during deployment.