io.github.nikolausm/imap-mcp-server

What we checked

Six static checks, weighted by risk. Every result reflects only what could be observed in the published package and repository — never intent.

• Injection surface

  fail25% of grade

  Tool descriptions/manifest scanned for instruction-injection patterns (imperatives at the model, hidden text, 'ignore previous', data-exfil URLs).

  tool "imap_add_account" param "defaultBcc" description: names an outbound copy/exfil destination (BCC/exfil verb). tool "imap_update_account" param "defaultBcc" description: names an outbound copy/exfil destination (BCC/exfil verb). tool "imap_send_email" description: names an outbound copy/exfil destination (BCC/exfil verb). tool "imap_send_email" param name "bcc": names an outbound copy/exfil destination (BCC/exfil verb). tool "imap_send_email" param "bcc" description: names an outbound copy/exfil destination (BCC/exfil verb). tool "imap_save_draft" param name "bcc": names an outbound copy/exfil destination (BCC/exfil verb). tool "imap_save_draft" param "bcc" description: names an outbound copy/exfil destination (BCC/exfil verb). tool "imap_reply_to_email" description: names an outbound copy/exfil destination (BCC/exfil verb). tool "imap_reply_to_email" param name "bcc": names an outbound copy/exfil destination (BCC/exfil verb). tool "imap_reply_to_email" param "bcc" description: names an outbound copy/exfil destination (BCC/exfil verb). tool "imap_forward_email" description: names an outbound copy/exfil destination (BCC/exfil verb). tool "imap_forward_email" param name "bcc": names an outbound copy/exfil destination (BCC/exfil verb). tool "imap_forward_email" param "bcc" description: names an outbound copy/exfil destination (BCC/exfil verb). tool "imap_delete_email" description: cross-tool redirection ('instead of call…').

• Supply chain

  warn25% of grade

  Package provenance: namespace verification, repo linkage, maintainer count, account age, postinstall scripts, typosquat distance.

  dependency "open" is edit-distance 2 from popular package "boxen" (typosquat candidate)

• Credential hygiene

  fail15% of grade

  How the server takes secrets (env vs plaintext config vs hardcoded); secrets appearing in tool schemas.

  tool "imap_add_account" has a secret-shaped input parameter "password" — secrets must never be tool parameters (the model would supply/handle the credential). tool "imap_update_account" has a secret-shaped input parameter "password" — secrets must never be tool parameters (the model would supply/handle the credential). tool "imap_update_account" has a secret-shaped input parameter "smtpPassword" — secrets must never be tool parameters (the model would supply/handle the credential).

• Permission scope

  pass15% of grade

  Declared tools vs. breadth (filesystem, network, exec); flags shell-exec and unbounded filesystem access.

  No shell-exec, unbounded/sensitive filesystem, or download-and-run primitives found in scanned source. PASS = no static red flag. Static scanning is blind to code fetched or executed at runtime.

• Version behavior

  fail10% of grade

  Diff of tool definitions between versions; new permissions or changed descriptions in a patch release (the postmark-mcp class).

  vs prior 1.6.0 (major bump): new tool "imap_add_account" appeared; new tool "imap_update_account" touches a sensitive surface (email/exec/net/fs); new tool "imap_list_accounts" appeared; new tool "imap_remove_account" appeared; new tool "imap_connect" appeared; new tool "imap_disconnect" appeared; new tool "imap_test_account" appeared; new tool "imap_search_emails" touches a sensitive surface (email/exec/net/fs); new tool "imap_get_email" touches a sensitive surface (email/exec/net/fs); new tool "imap_upload_file" touches a sensitive surface (email/exec/net/fs); new tool "imap_download_attachment" touches a sensitive surface (email/exec/net/fs); new tool "imap_mark_as_read" touches a sensitive surface (email/exec/net/fs); new tool "imap_mark_as_unread" appeared; new tool "imap_flag_email" touches a sensitive surface (email/exec/net/fs); new tool "imap_unflag_email" touches a sensitive surface (email/exec/net/fs); new tool "imap_add_keyword" touches a sensitive surface (email/exec/net/fs); new tool "imap_remove_keyword" touches a sensitive surface (email/exec/net/fs); new tool "imap_delete_email" touches a sensitive surface (email/exec/net/fs); new tool "imap_move_email" touches a sensitive surface (email/exec/net/fs); new tool "imap_bulk_delete" touches a sensitive surface (email/exec/net/fs); new tool "imap_bulk_delete_by_search" touches a sensitive surface (email/exec/net/fs); new tool "imap_get_latest_emails" touches a sensitive surface (email/exec/net/fs); new tool "imap_send_email" whose description contains exfiltration/BCC phrase; new tool "imap_save_draft" touches a sensitive surface (email/exec/net/fs); new tool "imap_reply_to_email" whose description contains exfiltration/BCC phrase; new tool "imap_forward_email" whose description contains exfiltration/BCC phrase; new tool "imap_find_thread_messages" touches a sensitive surface (email/exec/net/fs); new tool "imap_find_email_by_message_id" touches a sensitive surface (email/exec/net/fs); new tool "imap_list_folders" touches a sensitive surface (email/exec/net/fs); new tool "imap_folder_status" appeared; new tool "imap_create_folder" appeared; new tool "imap_get_unread_count" appeared; new tool "imap_check_spam" touches a sensitive surface (email/exec/net/fs); new tool "imap_delete_spam" touches a sensitive surface (email/exec/net/fs); new tool "imap_domain_stats" appeared; new tool "imap_add_spam_domain" appeared; new tool "imap_remove_spam_domain" appeared; new tool "imap_add_whitelist_domain" appeared; new tool "imap_list_spam_domains" appeared; new tool "imap_delete_by_domain" touches a sensitive surface (email/exec/net/fs).

• Transport config

  unscannable10% of grade

  Remote servers: TLS and auth mode (none/token/OAuth). Local servers: whether the manifest indicates it phones home.

  local stdio server: no remote transport or auth surface, and no phone-home/telemetry signal found in source. Absence of transport findings is NOT a safety guarantee — phone-home hosts can be constructed at runtime and defeat static analysis.