[kmcginnes]

Summary

Client log text could carry DEL and C1 control characters that pino leaves raw, letting a terminal or log viewer reinterpret an entry.

User-facing: none

 app.post(CLIENT_LOG_PATH, ...)
-  logger[level]({ source: "client", clientLog: message }, "client log")
+  logger[level]({ source: "client", clientLog: escapeControlCharacters(message) }, "client log")

escapeControlCharacters in logging.ts rewrites U+007F–U+009F as \uXXXX. Pino's JSON serialization already escapes newlines and the other C0 characters, so those and backslashes are untouched. The length cap, 400 and 415 behavior are unchanged.

Evidence

Before: DEL and C1 characters reached the log entry as raw bytes.
After: app.test.ts sends U+007F, U+0080, U+0085 and U+009F and asserts \u007f, \u0080, \u0085, \u009f, plus a mixed message and a case that plain text, backslashes and newlines pass through.

Verified live: curl against a locally running proxy; no raw 0x7f or C1 bytes in the log output.

Merge Danger

Door: two-way

Impact: log text only

Related

• Follow-up to Send client logs to /logger as a JSON body (#2468)

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_{🤖 Written by an AI agent on my behalf.}

[kmcginnes]

Approve