---
id: "CVE-2026-3583"
kind: "vulnerability"
aliases: ["CVE-2026-3583"]
title: "OAuth2 token introspection cache keeps revoked tokens after revocation request"
severity: "low"
cvss: 3.1
epss: null
exploited: false
status: "open"
category: "other"
products: []
ecosystems: []
tags: ["authentication", "oauth2", "other"]
not_affected_if: ["default-config"]
published_at: "2026-10-28T20:17:24+00:00"
first_seen_at: "2026-10-28T20:35:10+00:00"
updated_at: "2026-10-28T20:36:20+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-3583", "first_seen_at": "2026-10-28T20:35:10+00:00"}]
---

# OAuth2 token introspection cache keeps revoked tokens after revocation request

When the allowed_scopes setting is enabled, the OAuth2 token introspection cache is not cleared right away after a token is revoked, so a revoked access token can be handed back to a client until the cache entry expires. The sources say the re-issued token is not accepted for API authorization, so the main effect is disrupted authentication, not unauthorized access.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- unknown

## Fix

- unknown

## Timeline

- 2026-10-28T20:35:10+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-3583

## From the sources

When the `allowed_scopes` configuration is enabled, the OAuth2 token introspection mechanism does not immediately invalidate a token in the cache after a revocation request. This results in a scenario where an access token that was introspected immediately before a revocation request may be returned again to the client after revocation, until the relevant cache entry is cleared.

The security consequence is that a revoked access token may be re-issued to the client during the cache lifetime. While the re-issued token is not treated as valid for API authorization, affected users may be unable to obtain a new valid access token until the cache is cleared, which can disrupt authentication flows.

---

_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_