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+# Security Policy
+
+[![Report a Vulnerability](https://img.shields.io/badge/Report%20a-Vulnerability-red)](https://github.com/UglyToad/PdfPig/security/advisories/new)
+
+_Last updated: 27 August 2025_
+
+Thanks for helping keep **PdfPig** and its users safe. This document explains how to report vulnerabilities, what’s in scope, how we triage, and guidance for safely using PdfPig with untrusted PDFs.
+
+## Supported Versions
+
+We provide security fixes for the latest release and, when feasible, the previous minor line.
+
+| Version | Supported          |
+| ------- | ------------------ |
+| 0.1.x   | :white_check_mark: |
+
+If you depend on older versions, please upgrade to receive security patches.
+
+## Reporting a Vulnerability
+
+Please report security issues **privately** so we can triage and prepare a fix before public disclosure.
+
+- **Preferred:** [GitHub Security Advisory](https://github.com/UglyToad/PdfPig/security/advisories/new)  
+- **Alternative:** If you cannot use advisories, open a blank issue and immediately email a maintainer with a link asking to convert it to a private advisory (do **not** include details in the public issue).
+
+When reporting, include:
+
+- A clear description of the issue and impact
+- A minimal PoC (e.g., a crafted PDF) if possible
+- Affected version(s) and your environment
+- Suggested fix or mitigation (if known)
+
+We do **not** operate a paid bug bounty. Responsible disclosure credit is gladly given unless you prefer to remain anonymous.
+
+## Coordinated Disclosure & Timelines
+
+We aim to:
+
+- Acknowledge your report within **7 business days**
+- Provide an initial triage outcome within **14–30 days**
+- Release a fix and advisory as soon as reasonably possible, based on severity and complexity
+
+We will request reasonable time for users to update before public disclosure. Please avoid public discussion until a fix and advisory are published.
+
+## Scope
+
+### In scope
+
+- Vulnerabilities in PdfPig code and release artifacts that could lead to:
+  - Memory corruption, crashes, or undefined behavior from crafted PDFs
+  - Denial of service (CPU, memory, decompression bombs) beyond reasonable resource expectations
+  - Path traversal / unsafe file writes if originating from PdfPig APIs
+  - Logic flaws that expose data or break documented expectations
+
+### Out of scope
+
+- Issues in downstream projects that consume PdfPig
+- Security problems caused by misuse of the API (e.g., writing unvalidated data to disk)
+- Vulnerabilities exclusively in third-party dependencies (please report upstream; we will still track and update)
+- Performance limitations that are not security issues
+- Feature requests
+
+## Triage & Severity
+
+We use CVSS v3.x as a guide to classify severity (Critical/High/Medium/Low).  
+Where appropriate, we will publish a GitHub Security Advisory and request a **CVE** via GitHub’s CNA flow.
+
+Priorities (roughly):
+
+1. Memory safety / RCE vectors  
+2. Sandbox escapes enabled by PdfPig behavior  
+3. DoS vectors (e.g., decompression bombs) that are not reasonably mitigable by consumers  
+4. Path traversal / unsafe file I/O originating from library defaults  
+5. Information disclosure through parsing quirks or metadata handling
+
+## Responsible Testing Guidelines
+
+- Do **not** test with live production systems.  
+- Use private repositories and data; avoid publicly posting PoCs before disclosure.  
+- If sharing a malicious/crafted PDF, consider a password-protected ZIP (password `infected`) via the private advisory flow.  
+- Don’t run automated scanners that create spam issues or PRs.