Spring Authorization Server versions 1.0.0 - 1.0.5, 1.1.0 - 1.1.5, 1.2.0 - 1.2.2 and older unsupported versions are susceptible to a PKCE Downgrade Attack for Confidential Clients.
Specifically, an application is vulnerable when a Confidential Client uses PKCE for the Authorization Code Grant.
An application is not vulnerable when a Public Client uses PKCE for the Authorization Code Grant.
Weakness
The product uses external input with reflection to select which classes or code to use, but it does not sufficiently prevent the input from selecting improper classes or code.
Affected Software
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Spring | Ubuntu | focal | * |
| Spring | Ubuntu | mantic | * |
| Spring | Ubuntu | oracular | * |
| Spring | Ubuntu | plucky | * |