Priviged Escalation in Google Cloud Platform's Guest-OSLogin
Published Jun 22, 2020
7.3
HIGHCVSS 4.0
EPSS 0.32%
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.
Affected products
-
- Version 20190304StatusaffectedConstraints<20200507
- Version 20200507StatusunaffectedConstraints-
- Version
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Google LLC | Guest-Oslogin | unaffected |
|
No data.
No Red Hat product state for this CVE.
No package ranges for this CVE.
Remediation
No remediation recorded yet.
References (5)
- http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00037.html vendor-advisoryx_refsource_SUSEMailing ListThird Party Advisory
- http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00047.html vendor-advisoryx_refsource_SUSEMailing ListThird Party Advisory
- https://cloud.google.com/support/bulletins/#gcp-2020-008 x_refsource_MISCVendor Advisory
- https://github.com/GoogleCloudPlatform/guest-oslogin/pull/29 x_refsource_CONFIRMPatchThird Party Advisory
- https://gitlab.com/gitlab-com/gl-security/gl-redteam/red-team-tech-notes/-/tree/master/oslogin-privesc-june-2020 x_refsource_MISCExploitThird Party Advisory
| Link | Providers | Tags |
|---|---|---|
| http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00037.html | vendor-advisoryx_refsource_SUSEMailing ListThird Party Advisory | |
| http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00047.html | vendor-advisoryx_refsource_SUSEMailing ListThird Party Advisory | |
| https://cloud.google.com/support/bulletins/#gcp-2020-008 | x_refsource_MISCVendor Advisory | |
| https://github.com/GoogleCloudPlatform/guest-oslogin/pull/29 | x_refsource_CONFIRMPatchThird Party Advisory | |
| https://gitlab.com/gitlab-com/gl-security/gl-redteam/red-team-tech-notes/-/tree/master/oslogin-privesc-june-2020 | x_refsource_MISCExploitThird Party Advisory |
Change history (0)
No recorded changes yet.