SECURITY AND PRIVACY / Trail of Bits
Variant Analysis
Expands a confirmed vulnerability into related-code searches while preserving root-cause evidence and triage decisions.
“Hunts for the other instances of a bug already found — the variants of one root cause across a codebase. Use immediately after a vulnerability, logic bug, or bad pattern turns up in a specific file and the question becomes where else it occurs, including the bare conversational form ("are there others like this?", "is this the same bug?"). Also for generalizing one known instance into a CodeQL or Semgrep query for its whole pattern family, and for triaging a set of look-alike candidates against a known root cause. Not for initial discovery with no bug in hand.”
01 / THE REASONING
Why this made the selection.
- Starts from a verified instance and broadens one abstraction at a time, with explicit false-positive review.
- Bundles root-cause, search, triage and reporting references plus CodeQL and Semgrep starting templates.
02 / THE REVIEW RECORD
What we actually inspected.
Source review has boundaries.
A clear record is more useful than a “safe” badge.
Material inspected
- Full SKILL.md
- Root-cause, searching, triage and reporting references
- Bundled query and report templates
- LICENSE
Our findings
- The workflow distinguishes exact matching from broader pattern searches and requires manual candidate triage.
- The definition orders exact-match baselining before broader search and treats candidate triage, failed patterns and regression detection as explicit outputs.
- Steps 3 and 4 change one element at a time and stop when more than half the matches are noise.
Not established by this review
- No end-to-end agent session, effectiveness benchmark or target-project security assessment was run.
- No upstream installer, helper script or generated workload was executed.
The review applies to the material and revision named here. A newer upstream release can change its behavior.
03 / PUT IT TO WORK
Add a skill to your workflow.
DOCUMENTED COMMAND
npx skills add trailofbits/skills/plugins/variant-analysis/skills/variant-analysis --skill variant-analysisRun in your terminal to choose your AI tools, project or global scope, and installation method. This short command follows the current upstream version; the review covers the revision shown above.
Optional: install the reviewed revision
Keeps the original source and installer version where recorded, while leaving your AI tools and installation scope for you to choose.
npx skills add https://github.com/trailofbits/skills/tree/82fe8226252622fa807643bdca1710901198553a/plugins/variant-analysis/skills/variant-analysis --skill variant-analysis- Inspect the selected skill version and its supporting files before installation.
- Run the command in your terminal; choose your AI tools and project or global scope in the installer.
- Keep the complete skill directory and its licence. Install any task-specific tools separately and test on a small authorized example.
Before you start
- Node.js and npm for the Skills CLI
- An Agent Skills compatible coding assistant
- A confirmed seed defect and access to its code context
- CodeQL or Semgrep when using those optional templates
04 / FOLLOW THE EVIDENCE
The source trail.
Our notes are separate from the original resource.
Check upstream before adopting a new version.
https://github.com/trailofbits/skills/blob/82fe8226252622fa807643bdca1710901198553a/plugins/variant-analysis/skills/variant-analysis/SKILL.md
Supports: summary, upstreamDescription, whySelected, bestFor, limitations, review, access
https://github.com/trailofbits/skills/blob/82fe8226252622fa807643bdca1710901198553a/LICENSE
Supports: license, access.cost
https://github.com/vercel-labs/skills#readme
Supports: install, compatibility