Description
In OpenStack Keystone before 29.0.3, tokens obtained via delegated authentication mechanisms (OAuth1 access tokens, application credentials, trusts) could be submitted to the token-method authentication path for reauthentication to escape their intended project scope. When an application credential token was presented with no explicit scope, Keystone would issue a new token scoped to the credential owner's default project rather than the project for which the credential was issued, bypassing the intended project boundary. All Keystone deployments that permit delegated authentication through OAuth1 access tokens, application credentials, or trusts are affected.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| OpenStack | Keystone | 13.0.0 – < 27.0.3, 28.0.0 – < 28.0.3, 29.0.0 – < 29.0.3 | 27.0.3 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | keystone | 2:29.0.2-1 | — |
| Debian 13 | keystone | 2:27.0.0-3+deb13u5 | — |
| Debian 12 | keystone | 2:22.0.2-0+deb12u4 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.04 LTS | keystone | 2:29.0.0-0ubuntu1.4 | USN-8854-1 |
| Ubuntu 24.04 LTS | keystone | 2:25.0.0-0ubuntu1.6 | USN-8854-1 |
| Ubuntu 22.04 LTS | keystone | 2:21.0.1-0ubuntu2.6 | USN-8854-1 |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 20.04 LTS | keystone | 2:17.0.1-0ubuntu2+esm2 | USN-8854-1 |
| Ubuntu Pro 18.04 LTS | keystone | 2:13.0.4-0ubuntu1+esm1 | USN-8854-1 |
| Ubuntu Pro 16.04 LTS | keystone | 2:9.3.0-0ubuntu3.2+esm2 | USN-8854-1 |
Advisories 1
- USN-8854-1 keystone vulnerabilities Ubuntu Security Notices (USN) · Oct 1, 2026
References
- https://launchpad.net/bugs/2158538 issue-tracking
- https://security.openstack.org/ossa/OSSA-2026-037.html vendor-advisory
- https://www.openwall.com/lists/oss-security/2026/08/25/5 vendor-advisory mailing-list