CVE-2026-43965

Path Traversal in build/packages/packages.toml Allows Arbitrary Directory Deletion

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Published Jun 2, 2026 CVSS 4.0 · 5.6 Medium EPSS < 1% KEV · Not listed
Description
Path traversal vulnerability in Gleam's dependency management allows arbitrary directory deletion via malicious build/packages/packages.toml content.

Package keys read from build/packages/packages.toml by LocalPackages::read_from_disc are passed without validation to paths.build_packages_package(), which constructs a filesystem path by joining the project build directory with the attacker-controlled key. The resulting path is then passed to fs::delete_directory (which calls remove_dir_all). No check is performed to ensure the path remains within the intended build/packages/ directory. Both absolute paths and relative traversal sequences (e.g. ../) are accepted as package keys, allowing deletion of arbitrary directories.

An attacker who can cause a victim to run gleam deps download on a project containing a malicious build/packages/packages.toml (e.g. by committing the normally-gitignored file to a repository) can cause arbitrary directories on the victim's system to be recursively deleted.

This issue affects gleam: from 0.18.0-rc1 before 1.17.0.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

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History
Type Values Removed Values Added
Description Path traversal vulnerability in Gleam's dependency management allows arbitrary directory deletion via malicious build/packages/packages.toml content. Package keys read from build/packages/packages.toml by LocalPackages::read_from_disc are passed without validation to paths.build_packages_package(), which constructs a filesystem path by joining the project build directory with the attacker-controlled key. The resulting path is then passed to fs::delete_directory (which calls remove_dir_all). No check is performed to ensure the path remains within the intended build/packages/ directory. Both absolute paths and relative traversal sequences (e.g. ../) are accepted as package keys, allowing deletion of arbitrary directories. An attacker who can cause a victim to run gleam deps download on a project containing a malicious build/packages/packages.toml (e.g. by committing the normally-gitignored file to a repository) can cause arbitrary directories on the victim's system to be recursively deleted. This issue affects Gleam from 0.18.0-rc1 until 1.17.0. Path traversal vulnerability in Gleam's dependency management allows arbitrary directory deletion via malicious build/packages/packages.toml content. Package keys read from build/packages/packages.toml by LocalPackages::read_from_disc are passed without validation to paths.build_packages_package(), which constructs a filesystem path by joining the project build directory with the attacker-controlled key. The resulting path is then passed to fs::delete_directory (which calls remove_dir_all). No check is performed to ensure the path remains within the intended build/packages/ directory. Both absolute paths and relative traversal sequences (e.g. ../) are accepted as package keys, allowing deletion of arbitrary directories. An attacker who can cause a victim to run gleam deps download on a project containing a malicious build/packages/packages.toml (e.g. by committing the normally-gitignored file to a repository) can cause arbitrary directories on the victim's system to be recursively deleted. This issue affects gleam: from 0.18.0-rc1 before 1.17.0.
References
Type Values Removed Values Added
First Time appeared Gleam
Gleam gleam
Vendors & Products Gleam
Gleam gleam
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}
Type Values Removed Values Added
Description Path traversal vulnerability in Gleam's dependency management allows arbitrary directory deletion via malicious build/packages/packages.toml content. Package keys read from build/packages/packages.toml by LocalPackages::read_from_disc are passed without validation to paths.build_packages_package(), which constructs a filesystem path by joining the project build directory with the attacker-controlled key. The resulting path is then passed to fs::delete_directory (which calls remove_dir_all). No check is performed to ensure the path remains within the intended build/packages/ directory. Both absolute paths and relative traversal sequences (e.g. ../) are accepted as package keys, allowing deletion of arbitrary directories. An attacker who can cause a victim to run gleam deps download on a project containing a malicious build/packages/packages.toml (e.g. by committing the normally-gitignored file to a repository) can cause arbitrary directories on the victim's system to be recursively deleted. This issue affects Gleam from 0.18.0-rc1 until 1.17.0.
Title Path Traversal in build/packages/packages.toml Allows Arbitrary Directory Deletion
First Time appeared Gleam-lang
Gleam-lang gleam
Weaknesses CWE-22
CPEs cpe:2.3:a:gleam-lang:gleam:*:*:*:*:*:*:*:*
Vendors & Products Gleam-lang
Gleam-lang gleam
References
Metrics cvssV4_0

{'score': 5.6, 'vector': 'CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N'}
Weaknesses

Sources

Status
PUBLISHED
Assigner
EEF
Published
Updated
Nov 10, 2026, 7:19 PM
Reserved
May 4, 2026, 6:23 PM

View source JSON

Updated
Jun 2, 2026, 3:07 PM

JSON

Status
Deferred
Published
Jun 2, 2026, 2:16 PM
Modified
Nov 10, 2026, 8:19 PM

View source JSON

No data.

Updated
Jun 2, 2026, 3:45 PM

JSON