[Audit] Sanitize Error.message in API error responses

[RaminNietzsche]

Background

Error responses leak implementation detail.

Problem

Multiple handlers return raw Error.message to clients (K8s discovery, OPA/policy, jobs, tenants, SBOM) — exposing cluster URLs, kube errors, driver strings.

Proposed solution

• Shared toPublicError(err) mapping to stable codes + generic messages
• Log full error server-side only
• Audit handlers for err.message passthrough

Acceptance criteria

• 5xx/502 bodies lack stack/host/path internals
• Tests assert sanitized messages for representative handlers

Priority

P1 / Medium

Complexity

Small

Evidence

server/handlers/k8sDiscoveryHandlers.ts, policyHandlers.ts, jobHandlers.ts, tenantHandlers.ts, sbomHandlers.ts

[github-actions]

The issue highlights a security concern where raw Error.message content is returned in API error responses, potentially exposing sensitive details such as cluster URLs and driver strings. The proposed solution involves introducing a toPublicError(err) function to map errors to sanitized, stable codes and messages, logging full details server-side while ensuring client-facing responses omit internal details. An audit of handlers and additional tests will ensure compliance, with a goal of preventing sensitive data leaks in error responses.