PKCE Downgrade Attack

2024-03-2107:09:38

Veracode Vulnerability Database

sca.analysiscenter.veracode.com

pkce downgrade

authorization code grant

vulnerability

confidential clients

public clients

spring security

CVSS3

6.1

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

NONE

User Interaction

REQUIRED

Scope

CHANGED

Confidentiality Impact

LOW

Integrity Impact

LOW

Availability Impact

NONE

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

AI Score

6.9

Confidence

High

EPSS

Percentile

9.0%

JSON

spring-security-oauth2-authorization-server is vulnerable to PKCE Downgrade. The vulnerability is due to improper handling of PKCE authorization when a Confidential Client requests an Authorization Code Grant. Note that this vulnerability only applies to Confidential Clients, Public Clients are unaffected.