Security Policy

Threat Model

Overview

Readest is a cross-platform e-reader (macOS, Windows, Linux, Android, iOS, Web) built on Next.js and Tauri. It processes user-supplied ebook files, syncs data to the cloud, integrates with external services (OPDS catalogs, KOReader, DeepL, Yandex), and handles user authentication.

Assets

Asset	Description
Ebook files	User-uploaded EPUB, MOBI, PDF, and other formats stored locally and in cloud storage
Reading progress & annotations	Highlights, bookmarks, and notes synced across devices
User credentials	Authentication tokens and session data for cloud sync
User preferences & settings	Reading preferences, custom fonts, theme configurations
External API keys	Translation service credentials (DeepL, Yandex) configured by users

Threat Actors

Actor	Motivation
Malicious ebook author	Craft a malformed file to exploit the parser or renderer
Network attacker (MitM)	Intercept sync traffic to steal credentials or inject data
Malicious OPDS server	Serve crafted catalog responses to exploit the client
Compromised dependency	Supply chain attack via npm or Cargo ecosystem
Unauthorized user	Access another user's synced library or annotations

Attack Surfaces & Mitigations

1. Ebook File Parsing

• Risk: Malformed EPUB/MOBI/PDF files could trigger parser bugs, path traversal, or script injection via embedded HTML/JS.
• Mitigations: Ebook content is rendered in a sandboxed iframe. External script execution is blocked. File parsing is isolated from the main process.

2. Cloud Sync & Authentication

• Risk: Credential theft, session hijacking, or unauthorized access to another user's library data.
• Mitigations: All sync traffic uses HTTPS/TLS. Authentication tokens are stored securely (OS keychain/secure storage). Server-side authorization ensures users can only access their own data.

3. OPDS / External Catalog Integration

• Risk: A malicious OPDS server could serve crafted XML to exploit the parser, or redirect downloads to malicious files.
• Mitigations: OPDS responses are parsed defensively. Users explicitly add catalog sources. Downloaded files are treated as untrusted user content.

4. Rendered HTML/JS in Ebook Content

• Risk: Embedded JavaScript in EPUB files could attempt XSS or data exfiltration.
• Mitigations: Book content is rendered in a sandboxed iframe with scripting restrictions. Navigation outside the book context is blocked.

5. Supply Chain

• Risk: Compromised npm or Cargo packages could introduce malicious code.
• Mitigations: Dependencies are pinned via pnpm-lock.yaml and Cargo.lock. Dependabot and GitHub's dependency review are enabled for automated vulnerability detection.

6. Desktop Native Code (Tauri)

• Risk: Tauri IPC commands could be abused by malicious web content to access the filesystem or OS APIs.
• Mitigations: Tauri's allowlist restricts which IPC commands are exposed. File system access is scoped to the application data directory.

Out of Scope

• Vulnerabilities in user's operating system or browser outside of Readest's control
• Physical access attacks to a user's device
• Issues in third-party services (DeepL, Yandex, Calibre) themselves

Supported Versions

Readest does not currently maintain separate release channels. Security updates are provided only for the latest release series.

Version	Supported
0.10.x	✅
< 0.10	❌

Reporting a Vulnerability

Please report suspected vulnerabilities privately. Do not open a public GitHub issue or discussion for security-sensitive reports.

Use GitHub's private vulnerability reporting for this repository:

https://github.com/readest/readest/security/advisories/new

When submitting a report, include:

• A clear description of the issue and the affected component
• Steps to reproduce, proof of concept, or a minimal test case
• The versions, platforms, or environments you tested
• Any suggested remediation or mitigating details, if available

What to expect after you report:

• We will aim to acknowledge receipt within 3 business days.
• We may contact you for additional details, reproduction steps, or validation.
• If the report is accepted, we will work on a fix and coordinate disclosure.
• If the report is declined, we will explain why, for example if the behavior is expected, unsupported, or not reproducible.

Please keep vulnerability details private until a fix is available and the maintainers have approved disclosure.

Incident Response Plan

When a security vulnerability is confirmed, we follow this process:

1. Triage (Day 1–2)

• Assign a severity level (Critical / High / Medium / Low) based on impact and exploitability.
• Identify affected versions, components, and users.
• Assign an owner responsible for coordinating the response.

2. Containment (Day 1–3)

• Assess whether an immediate mitigation or workaround can be published.
• Limit further exposure where possible (e.g., disable affected features, update dependencies).

3. Remediation (Day 3–14, depending on severity)

• Develop and internally review a fix.
• Validate the fix does not introduce regressions.
• Prepare a patched release and update changelog.

4. Disclosure & Release

• Coordinate disclosure timing with the reporter.
• Publish a GitHub Security Advisory with CVE if applicable.
• Release the patched version and notify users via release notes.

5. Post-Incident Review

• Document the root cause, timeline, and resolution.
• Update processes or controls to prevent recurrence.

Severity Definitions

Severity	Description
Critical	Remote code execution, full data compromise, or authentication bypass
High	Significant data exposure, privilege escalation, or denial of service
Medium	Limited data exposure or functionality disruption
Low	Minor issues with minimal security impact