OSSA-2020-004: Keystone credential endpoints allow owner modification and are not protected from a scoped context

Date:

May 06, 2020

CVE:

CVE-2020-12689, CVE-2020-12691

Affects

• Keystone: <15.0.1, ==16.0.0

Description

kay reported two vulnerabilities in keystone’s EC2 credentials API. Any authenticated user could create an EC2 credential for themselves for a project that they have a specified role on, then perform an update to the credential user and project, allowing them to masquerade as another user. (CVE-2020-12691) Any authenticated user within a limited scope (trust/oauth/application credential) can create an EC2 credential with an escalated permission, such as obtaining admin while the user is on a limited viewer role. (CVE-2020-12689) Both of these vulnerabilities potentially allow a malicious user to act as admin on a project that another user has the admin role on, which can effectively grant the malicious user global admin privileges.

Errata

CVE-2020-12689 and CVE-2020-12691 were assigned after the original publication date.

Patches

• https://review.opendev.org/725895 (Rocky)

• https://review.opendev.org/725893 (Stein)

• https://review.opendev.org/725891 (Train)

• https://review.opendev.org/725888 (Ussuri)

• https://review.opendev.org/725886 (Victoria)

Credits

• kay (CVE-2020-12689, CVE-2020-12691)

References

• https://launchpad.net/bugs/1872733

• https://launchpad.net/bugs/1872735

• http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-12689

• http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-12691

Notes

• The stable/rocky branch is under extended maintenance and will receive no new point releases, but a patch for it is provided as a courtesy.

OSSA History

• 2020-05-07 - Errata 1

• 2020-05-06 - Original Version