CVE-2026-52769 — YesWiki is a wiki system written in PHP.¶

Key facts

CVE-2026-52769 is a High (8.3) vulnerability: YesWiki is a wiki system written in PHP.. This entry ships a detection-only PoC and a Docker test lab.


CVE	CVE-2026-52769
Severity	High (8.3)
Detection / prevention	—
PoC	poc.py
Source	2026/CVE-2026-52769/

Details¶

English | 한국어

Description¶

YesWiki is a wiki system written in PHP. From version 4.6.2 to before version 4.6.6, the POST /api/forms/{formId}/actor/inbox route - exposed publicly with acl:"public" - accepts an HTTP Signature header whose keyId parameter is a URL. HttpSignatureService::verifySignature() parses the header and immediately makes a server-side HTTP GET to that URL, before any cryptographic verification or URL validation. An unauthenticated remote attacker can therefore make YesWiki issue arbitrary outbound HTTP requests to any host the server can reach - internal services, cloud-metadata endpoints (169.254.169.254), intranet-only admin panels, etc. - and read enough back via timing and error-message oracles to scan ports, enumerate services, and (on a real cloud instance) reach IAM metadata. The only deployment-side precondition is that ActivityPub be enabled on at least one Bazar form. This issue has been patched in version 4.6.6.

Vulnerability Details¶

Property	Value
CVE ID	CVE-2026-52769
Type	SSRF
CVSS Score	8.3

Proof of Concept¶

Download¶

# Download PoC script
curl -O https://raw.githubusercontent.com/fankh/vulnerability-poc/main/2026/CVE-2026-52769/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-2026-52769

# 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¶

http://github.com/YesWiki/yeswiki/commit/87e627f33e79879827a3669fee2aa1244612c487
https://github.com/YesWiki/yeswiki/releases/tag/v4.6.6
https://github.com/YesWiki/yeswiki/security/advisories/GHSA-vw42-752g-5mrp

Generated by PoC Generator on 2026-09-05T11:26:25.957463584

Frequently asked questions¶

What is CVE-2026-52769?¶

CVE-2026-52769 is a High (8.3) vulnerability: YesWiki is a wiki system written in PHP.. This entry ships a detection-only PoC and a Docker test lab.

How do I detect CVE-2026-52769?¶

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-2026-52769?¶

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.