CVE-2026-100627 — Capgo (Cap-go/capgo.app) server backend Supabase functions contain an incorrect…¶

Key facts

CVE-2026-100627 is a High (8.1) vulnerability: Capgo (Cap-go/capgo.app) server backend Supabase functions contain an incorrect…. This entry ships a detection-only PoC and a Docker test lab.


CVE	CVE-2026-100627
Severity	High (8.1)
Detection / prevention	—
PoC	poc.py
Source	2026/CVE-2026-100627/

Details¶

English | 한국어

Description¶

Capgo (Cap-go/capgo.app) server backend Supabase functions contain an incorrect authorization flaw in the API-key bundle promotion path. The PUT /bundle endpoint, available to "all" and "write" API keys, dispatches to setChannel, which authorizes with checkPermission(c, 'channel.promote_bundle', { appId: body.app_id }) and omits the request's channel_id. Because the omitted scope field is passed to rbac_check_permission_direct as SQL NULL, and channel-scope override evaluation is gated on p_channel_id IS NOT NULL, per-channel allow/deny overrides are never evaluated. A principal holding app-level channel.promote_bundle (granted by default to the app_developer and app_uploader roles) can therefore promote a bundle to a channel for which an explicit per-channel deny override exists, updating public.channels.version for the supplied channel_id; the target channel is only validated after authorization. The issue is confirmed on main at commit de66fa51e7ff2f50283cc1455c3d80ab3eb0ae43 and likely earlier versions; no patched version is known at the time of publication.

Vulnerability Details¶

Property	Value
CVE ID	CVE-2026-100627
Type	IDOR
CVSS Score	8.1

Proof of Concept¶

Download¶

# Download PoC script
curl -O https://raw.githubusercontent.com/fankh/vulnerability-poc/main/2026/CVE-2026-100627/poc.py

Usage¶

# Run PoC against target
python3 poc.py --target <TARGET_URL>

# With authentication
python3 poc.py --target <TARGET_URL> --username <USER> --password <PASS>

⚠️ Warning: This PoC is for authorized security testing only. It uses detection-only techniques and does not exploit or damage target systems.

Test Lab¶

This repository includes a Docker-based test environment with both vulnerable and patched applications.

Quick Start¶

# Clone and navigate to CVE directory
cd CVE-2026-100627

# Start both applications
docker-compose up -d

# Run tests
./run-tests.sh    # Linux/Mac
./run-tests.ps1   # Windows PowerShell

Application Endpoints¶

Application	URL	Status
Vulnerable App	http://localhost:8080	Shows vulnerability
Patched App	http://localhost:8081	Demonstrates fix

Directory Structure¶

├── README.md           # English documentation
├── README_KO.md        # Korean documentation
├── poc.py              # PoC detection script
├── docker-compose.yml  # Container orchestration
├── run-tests.sh        # Linux/Mac test runner
├── run-tests.ps1       # Windows test runner
├── vulnerable-app/     # Vulnerable version
│   ├── app.py
│   ├── Dockerfile
│   └── requirements.txt
└── patched-app/        # Fixed version
    ├── app.py
    ├── Dockerfile
    └── requirements.txt

References¶

https://github.com/Cap-go/capgo.app/security/advisories/GHSA-633x-9x77-77gf
https://www.vulncheck.com/advisories/capgo-bundle-promotion-api-channel-rbac-deny-override-bypass

Generated by PoC Generator on 2026-09-27T04:49:36.159604799

Frequently asked questions¶

What is CVE-2026-100627?¶

CVE-2026-100627 is a High (8.1) vulnerability: Capgo (Cap-go/capgo.app) server backend Supabase functions contain an incorrect…. This entry ships a detection-only PoC and a Docker test lab.

How do I detect CVE-2026-100627?¶

Run the detection-only PoC included with this entry against your Docker test lab to confirm whether a target is affected; pair it with your own IDS logging.

How do I block or mitigate CVE-2026-100627?¶

Upgrade to a fixed version per the vendor advisory; the NVD record lists the affected versions. Use the included PoC to verify your remediation.

For authorized security testing and research only. See the full source and NVD record.