T09 · Insecure Skill Coding Practices
Warning
- Location
- scripts/send_feishu_voice.sh:3
- Finding
- Feishu Tenant Access Token Exposed Through Command-Line Arguments<![CDATA[ ## Vulnerability Details **File Location**: `scripts/send_feishu_voice.sh:3-10` **Vulnerability Type**: Sensitive credential exposure through process arguments **Risk Level**: Medium ### Vulnerable Code ```bash # Usage: send_feishu_voice.sh <ogg_file> <receive_id> <tenant_access_token> [receive_id_type] # receive_id_type: open_id (default), chat_id, user_id, union_id, email set -e OGG_FILE="$1" RECEIVE_ID="$2" TOKEN="$3" ``` The corresponding invocation documented in `SKILL.md:49` is: ```bash scripts/send_feishu_voice.sh /tmp/voice.ogg <receive_id> <tenant_access_token> [receive_id_type] ``` ### Technical Analysis The Feishu tenant access token is supplied as the third command-line argument and copied into the `TOKEN` shell variable. Depending on the operating system and runtime environment, command-line arguments may be exposed through process inspection facilities, diagnostic tools, audit systems, shell command history, CI/CD logs, or orchestration telemetry. Although access to another process's arguments may be restricted by operating-system policy, placing credentials in `argv` unnecessarily expands their exposure. The script only needs the credential in memory when constructing the Feishu authorization header; accepting it through a protected environment variable, file descriptor, or secret manager would reduce exposure. The script subsequently uses the credential as a bearer token: ```bash -H "Authorization: Bearer $TOKEN" ``` Possession of this token permits calls to Feishu APIs within the permissions granted to the associated application. ### Attack Path 1. A user invokes the documented command and supplies a valid tenant access token as the third argument. 2. While the process is active, a local user or monitoring component with sufficient visibility inspects the process command line. Alternatively, the command is retained in shell history, CI logs, or execution telemetry. 3. The observer extracts the tenant access token. 4. Th ...[truncated 619 chars]
- Remediation
- <![CDATA[ ## Remediation Suggestions - Remove the tenant token from positional command-line arguments. - Read it from a protected environment variable, a secret manager, or an inherited file descriptor. For example: ```bash TOKEN="${FEISHU_TENANT_ACCESS_TOKEN:-}" if [ -z "$TOKEN" ]; then echo "FEISHU_TENANT_ACCESS_TOKEN is required" >&2 exit 1 fi ``` - Update `SKILL.md` so examples do not place secrets directly in command lines. - Prevent commands containing secrets from being written to shell history or CI/CD logs. - Ensure secret values are redacted from diagnostic output. - Grant the Feishu application only the API scopes needed to upload and send audio messages. - Rotate or revoke any token suspected of having been logged or exposed. ]]>