CVE-2026-42795

What it is

Symlink following vulnerability in Gleam's Hex package export allows files outside the project root to be embedded in the generated package tarball. The file collection helpers (gleam_files, native_files, private_files) in compiler-cli/src/fs.rs use follow_links(true) when walking publishable directories such as src/ and priv/. The collected paths are added to the package archive via add_path_to_tar in compiler-cli/src/publish.rs without verifying that the resolved target remains within the project root. A symlink placed under a publishable directory will cause gleam export hex-tarball or gleam publish to embed the contents of the symlink target into the generated Hex package. An attacker with write access to the project repository can place a symlink in src/ or priv/ pointing to an arbitrary file. When a maintainer or CI pipeline runs gleam publish or gleam export hex-tarball, local files readable by the publisher (such as secrets, tokens, or SSH keys) are silently embedded into the published package artifact. This issue affects Gleam from 0.10.0-rc1 until 1.17.0.

At a glance

Exploitability

Can be exploited locally on the machine with a low-privilege account, but needs a user to act. High risk of data exposure.

Exploit odds

0.2% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2026-06-02 14:16 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-10-06 22:10 UTC Last updatedMost recent change to the record

Why it ranks here

• Exploited in the wild: no, CISA does not list it.
• Exploit odds: 0.2% in the next 30 days (EPSS).
• Severity: 5.1 MEDIUM (CVSS).
• Fix: a patch or advisory is linked.

Details

Published

2026-06-02 14:16 UTC

Last modified

2026-10-06 22:10 UTC

Exploit probability

0.2% · EPSS, next 30 days

Weakness

CWE-59

Record status

Deferred

Attack profile CVSS 4.0 · 5.1

Attack vector

Local

Complexity

Low

Attack requirements

None

Privileges needed

Low

User interaction

Active

Confidentiality

High

Integrity

None

Availability

None

Is it in your code?

Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.

Read https://cve-list.com/agent/cve/CVE-2026-42795.md and follow it. Check whether this project is affected by CVE-2026-42795. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.

Copy as ticket · More options · Status badge