# exceptional-conditions

> Claude/Codex skill by [@thejefflarson](https://omgskills.com/library/thejefflarson/index.md) · 20 stars · Updated 2026-07-31

Detects error handlers that leak stack traces or fail open on exception. Use when writing error handlers, exception catching blocks, try/catch/finally constructs, or API error responses. Also invoke when an application could fail open on exception, or when stack traces might reach end users.

Tags: llms, security, skills

## Install

```sh
git clone https://github.com/thejefflarson/soundcheck /tmp/soundcheck && ln -s /tmp/soundcheck/.claude/skills/exceptional-conditions ~/.claude/skills/exceptional-conditions
```

## From README

Exceptional Conditions Security Check (A05:2025) What this checks Protects against information disclosure and fail-open logic. Stack traces in API responses leak internal paths, library versions, and logic for attackers to target; swallowed exceptions and default-allow error paths grant unintended access. Vulnerable patterns Error handler that returns the raw exception message, stack trace, or internal path in the HTTP response body Catch block that silently swallows exceptions with no logging, re-raise, or controlled error Authorization or permission exception caught and turned into a success or fall-through that grants access Debug or verbose-error flag enabled at deployment, exposing tracebacks to clients Default framework error page left in place, leaking file paths, library versions, or framework banner Fix immediately Flag the vulnerable code and explain the risk. Then suggest a fix that establishes these properties: Client responses carry no internal detail.

## Links

- HTML page: https://omgskills.com/library/thejefflarson/soundcheck/dot-claude/skills/exceptional-conditions/
- GitHub: https://github.com/thejefflarson/soundcheck
- Author: [@thejefflarson](https://omgskills.com/library/thejefflarson/index.md)

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