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Sean WhalenandClaude Fable 5.1
09c88ca2a3
* Harden failure-report sample filenames and cap decompressed report size Fixes the two open security advisories. GHSA-c284-w5m6-jhjm (path traversal, affects 9.0.6 through 11.0.0): save_output() named each failure report's message sample after the sample's Subject header, falling back to the raw subject whenever sanitizing it produced an empty string. A subject of only path separators and dots -- "../../../" or "/" -- sanitizes to "", so the raw value reached os.path.join() and the .eml landed outside the samples directory or at an absolute path. That subject comes from a message that failed authentication, so any sender a monitored mailbox accepts controls it. The name is now sanitized at write time and falls back to "sample", and the caller-supplied filename_safe_subject key is no longer trusted. get_filename_safe_string() also strips NUL (which would otherwise make open() raise ValueError: embedded null byte and hold back the whole mailbox batch), truncates before stripping trailing characters, and strips trailing spaces along with trailing dots, since Windows drops both when creating a file; its docstring now states the guarantees callers depend on. GHSA-43qf-f35w-2x4r (unbounded decompression, affects all versions through 11.0.0): extract_report() inflated gzip with one unbounded zlib.decompress() and read zip members with an unbounded .read(). The attachment's content is chosen by its sender, and deflate reaches about 1000:1 on degenerate input, so a 100 KB attachment inflated to 100 MB with a ~209 MiB peak. Extraction now stops at MAX_DECOMPRESSED_REPORT_SIZE (100 MiB) and raises ParserError. The gzip path moves to a zlib.decompressobj() bounded by max_length, which does not raise on a stream that ends early the way the one-shot call did, so the helper checks decompressor.eof itself; a stream with trailing bytes after the gzip member still extracts, matching the old behavior. Both behaviors were observed against the unmodified code first and are pinned by tests. Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com> * Strip NUL from CSV fields so Python 3.10's csv writer accepts them Python 3.10's csv writer raises _csv.Error: need to escape, but no escapechar set on any field containing NUL (CPython issue 97503, a 3.10 regression fixed in 3.11+). Failure report text fields (subject, user agent, authentication results, addresses, etc.) come from untrusted mail, so a NUL byte in one made parsed_failure_reports_to_csv() -- and therefore save_output() -- raise on 3.10, which the CLI's except (OSError, ValueError) around save_output does not catch. NUL is now stripped from every CSV field on all Python versions via a shared _csv_safe() helper, applied in all three CSV writers, so output is identical regardless of interpreter version. Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com> * 11.0.1 release: bump version and finalize changelog Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com> --------- Co-authored-by: Claude Fable 5.1 <noreply@anthropic.com>