Please report suspected vulnerabilities privately via GitHub's "Report a vulnerability" (Security → Advisories → Report) on this repository. Do not open a public issue for exploitable problems.

Include, where possible:

• affected version/commit and browser version;
• a minimal reproduction (policy JSON or "My rules" text plus steps);
• impact assessment: what can an attacker achieve, from which position (malicious website, malicious policy import, compromised list file)?

You can expect an acknowledgement within 7 days. Coordinated disclosure is appreciated; we will credit reporters unless they prefer otherwise.

Examples of reports we consider security-relevant:

• A page or frame that can bypass a committed block/cookie/CSP rule in a way not documented as an MV3 limitation.
• Policy import (JSON or rules text) leading to code execution, HTML injection in the UI, or rule injection beyond what the imported policy legitimately expresses.
• A crafted website able to read or modify VIGIL's stored policy.
• Priority-ladder flaws where a less specific rule silently defeats a more specific one (the invariants in docs/ARCHITECTURE.md are normative).
• The blocklist build tool producing rules that differ from the input list in an exploitable way.

These are known consequences of the MV3 design, documented in docs/ARCHITECTURE.md and DISCLAIMER.md:

• Requests VIGIL never saw (fired before rules existed, or outside DNR's reach) are not blocked retroactively.
• Removing a committed cookie block via a draft takes effect only after Save.
• getMatchedRules quota limits the matched-rules viewer; there are no live per-cell counters.
• First-party pages can technically evade classification heuristics in the scanner; enforcement is done by DNR conditions, not by the scanner.
• Tracking via mechanisms DNR cannot see (e.g. first-party server-side tracking) is out of scope.

• The extension has zero runtime dependencies and zero build-time npm dependencies; the test suite uses only node:test.
• No remote code or remote configuration is loaded, in line with MV3 policy.
• Releases are tagged; the published zip should be reproducible from the tag (git archive equivalence). Please report any release artifact that does not match its tag.