Intensive end-to-end testing (a live gateway-MCP <-> agent integration harness +
an adversarial redaction/abuse probe + an independent security audit) surfaced
three real issues in the shipped read-only diagnostic agent. All run in lib/**,
which is packaged in the app.
1. grep ReDoS froze the Electron main process. read_log compiled the
client-supplied grep into `new RegExp(grep, 'i')` and ran it synchronously over
the log tail IN the main process. A catastrophic pattern (e.g. "(a+)+$" against
a long line) hangs the whole app — empirically confirmed (8s timeout, killed).
JS regex is synchronous and uncancellable, so grep is now a case-insensitive
literal substring filter with "|" alternation ("error|timeout|502"). Provably
linear-time; covers the real diagnostic need.
2. Prototype-chain whitelist bypass. The op table was a plain object literal, so
handle("constructor" | "toString" | "valueOf", ...) resolved an inherited
Object.prototype function, passed the `typeof fn === 'function'` guard and
returned {ok:true}. Harmless functions today, but a whitelist-integrity hole.
Now guarded with a string check + Object.prototype.hasOwnProperty.
3. Redaction defense-in-depth gaps. redactLogText now also scrubs: basic-auth URL
passwords (scheme://user:pass@host), Authorization: Basic, JWTs (eyJ...x.y.z),
and bare/JSON session= values. Mostly theoretical in today's readable logs
(secret-bearing bodies go to the excluded doodstream-debug.log; other hosters
throw static strings) but matters as the verbose-logging surface grows.
Verified: 383 app tests (incl. new regression tests for all three), the live
gateway-MCP integration harness (all 14 tools, zero leaks, error paths), the
adversarial probe (14/14+ secret shapes scrubbed, ReDoS 1ms, lockout, malformed
args), e2e gate, lint 0 errors. Only residual: a standalone high-entropy blob with
zero key/Bearer/URL context — inherent to any denylist, acknowledged.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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