spring-projects / spring-projects/spring-security

OIDC token-request client-secret %3D instead of = for padding

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#17,629 3 comments 2 reactions 0 assignees View on GitHub

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status: waiting-for-triage type: bug
Dominant language
Java
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Description

When sending an OIDC token-request including client-secret (and client-id), the configured client-secret is changed: Any ending = is converted to %3D

To Reproduce
authenticate against an OIDC provider that requires
spring.security.oauth2.client.registration.<provider>.client-authentication-method=client_secret_post
with a client-secret that ends with padding character =

That will result in a token-request where the padding character is replaced by unicode %3D

Expected behavior
padding character for client-id should not be converted to unicode

Contributor guide

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First steps

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Research direction

No source files or tests are named. Start by reproducing an OIDC token request using client_secret_post and a client-secret ending in =; done means the request preserves the padding character as = rather than encoding it as %3D.

Written by the indexing model from the issue text.

Assessment

Tech stack
java, spring
Domain
api, authentication, security
Issue type
Bug
Difficulty
3/5
Estimated time
1-2 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
35/100

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