GHSA-H4FR-CMH5-QR62

Fallow: A .* glob segment let an analyzed repository make Fallow test paths in the parent of the project root

Workarounds

Run Fallow only on repositories that you trust. Before you run Fallow on another repository, check the detection, configPatterns and alwaysUsed patterns of its plugin files.

Fallow expands some globs from the analyzed repository on disk. Before 3.34.0, a segment such as .*, .? or ..* in such a glob also matched the special .. entry. The glob crate tests .. against a segment that starts with a literal .. Fallow validates plugin glob patterns and refuses absolute paths and .. segments, but these segments passed that validation.

The attacker controls the repository content. The attacker must also be able to read the Fallow output, for example a CI log or a pull request comment. Then the attacker can learn if a file or directory exists in the parent of the project root:

• A plugin fileExists detection pattern such as .*/marker.json made the plugin active when marker.json existed in the parent directory.
• An external plugin configPatterns or alwaysUsed pattern could match a config file in the parent directory. When the plugin was active and declared toolingDependencies, the tooling detection credited the related dev dependency. An unused dependency finding could then disappear, and --trace-dependency printed the outside path.
• fallow plugin-check reported path_exists: true for a seeded entry that matched only in the parent directory.

Fallow tested only that these paths exist. It did not read or print the content of a file outside the project root through these globs.

The Jest, Vitest and Rstest project globs had the same .* problem, and the Jest and Vitest ones also read file content. GHSA-jfwm-3p3c-6hx5 describes that case.

Input manipulates file paths to reach files outside the intended directory, such as configuration or credential files. Typical impact: unauthorized file read or write outside the intended directory.

GHSA-H4FR-CMH5-QR62 has a CVSS score of 3.3 (Low). The vector is requires local access, no privileges required, and user interaction required. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (3.34.0); upgrading removes the vulnerable code path.

Kodem intelligence

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Fixed in 3.34.0. Fallow now rewrites a leading . in a wildcard segment to [.] before it expands the glob on disk. [.] matches the same hidden files and directories inside the project root. The glob crate does not test .. against it.

1. What is GHSA-H4FR-CMH5-QR62? GHSA-H4FR-CMH5-QR62 is a low-severity path traversal vulnerability in fallow (npm), affecting versions < 3.34.0. It is fixed in 3.34.0. Input manipulates file paths to reach files outside the intended directory, such as configuration or credential files.
2. How severe is GHSA-H4FR-CMH5-QR62? GHSA-H4FR-CMH5-QR62 has a CVSS score of 3.3 (Low). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
3. Which packages are affected by GHSA-H4FR-CMH5-QR62?
   • fallow (npm) (versions < 3.34.0)
   • @fallow-cli/fallow-node (npm) (versions < 3.34.0)
   • fallow-cli (rust) (versions < 3.34.0)
   • fallow-config (rust) (versions < 3.34.0)
   • fallow-core (rust) (versions < 3.34.0)
4. Is there a fix for GHSA-H4FR-CMH5-QR62? Yes. GHSA-H4FR-CMH5-QR62 is fixed in 3.34.0. Upgrade to this version or later.
5. Is GHSA-H4FR-CMH5-QR62 exploitable, and should I be worried? Whether GHSA-H4FR-CMH5-QR62 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
6. What actually determines whether GHSA-H4FR-CMH5-QR62 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
7. How do I fix GHSA-H4FR-CMH5-QR62?
   • Upgrade fallow to 3.34.0 or later
   • Upgrade @fallow-cli/fallow-node to 3.34.0 or later
   • Upgrade fallow-cli to 3.34.0 or later
   • Upgrade fallow-config to 3.34.0 or later
   • Upgrade fallow-core to 3.34.0 or later

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