postgres: raise detection threshold to prevent false positives (#125)#734
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postgres: raise detection threshold to prevent false positives (#125)#734Seanstoppable wants to merge 2 commits into
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) The postgres scanner could misidentify non-Postgres services as PostgreSQL when they responded with an 'N' byte (or any non-'E' response) to the version probe. This is the scenario described in issue zmap#125. Changes: - Version probes (0.0 and 255.255) now require the server to return a valid 'E'-type error packet. Any other response type causes the scan to bail with SCAN_PROTOCOL_ERROR. - Add isValidPostgresError() to validate that 'E' packets contain the minimum structured fields (severity, code, message) expected from a real PostgreSQL server. - Add tests for false-positive scenarios: bare 'N' byte, invalid error fields, immediate close, and valid server responses. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Older Postgres versions (e.g. 9.3-9.5) respond to bogus version probes with a raw \n\0-terminated error string rather than a structured 'E' packet with tagged fields. These have Length=0 in the parsed ServerPacket. Only apply isValidPostgresError validation to structured error packets (Length > 0). Pre-startup errors (Length == 0) are still accepted as valid Postgres detections since the 'E' type byte combined with the \n\0 termination is sufficient evidence. Add TestPreStartupError_OlderPostgres to cover this case. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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The postgres scanner could misidentify non-Postgres services as PostgreSQL when they responded with an 'N' byte (or any non-'E' response) to the version probe. This is the scenario described in issue #125.
Changes: