---
id: CVE-2026-79786
title: >-
  Coroot's unauthenticated MCP OAuth dynamic client registration endpoint
  accepts any syntactically valid redirect URI without validation, allowing
  attackers to register clients pointing to attacker-controlled hosts
summary: >-
  Coroot's unauthenticated MCP OAuth dynamic client registration endpoint
  accepts any syntactically valid redirect URI without validation, allowing
  attackers to register clients pointing to attacker-controlled hosts. Attackers
  can send aut…
severity: high
cvss: 7.1
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N'
cwe:
  - CWE-601
published: '2026-08-25'
updated: '2026-09-23'
sourceUpdated: '2026-09-23T17:17:43.030'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-79786'
references:
  - url: 'https://github.com/coroot/coroot'
    label: disclosure@vulncheck.com
  - url: 'https://github.com/coroot/coroot/blob/v1.24.5/api/mcp_oauth.go'
    label: disclosure@vulncheck.com
  - url: 'https://github.com/coroot/coroot/issues/929'
    label: disclosure@vulncheck.com
  - url: >-
      https://www.vulncheck.com/advisories/coroot-1.20.2-through-1.24.5-unvalidated-redirect-uri-in-mcp-oauth-client-registration
    label: disclosure@vulncheck.com
  - url: 'https://github.com/coroot/coroot/issues/929'
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
tags:
  - nvd
epss: 0.00219
epssPercentile: 0.12687
ingestedAt: '2026-08-29T21:42:33.765Z'
---

## Overview

Coroot's unauthenticated MCP OAuth dynamic client registration endpoint accepts any syntactically valid redirect URI without validation, allowing attackers to register clients pointing to attacker-controlled hosts. Attackers can send authorization URLs to signed-in users, capture their authorization codes upon consent approval, and exchange them for access tokens to hijack MCP sessions.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.