CVE-2026-42795

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.

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.

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.

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.

Summary

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.

Workarounds

* Avoid running gleam publish or gleam export hex-tarball on untrusted projects * Review the contents of src/ and priv/ for unexpected symlinks before publishing * Run publishing commands in a restricted or isolated environment (e.g. containers)

These are all security issues fixed in the gleam-1.17.0-1.1 package on the GA media of openSUSE Tumbleweed.

This update for gleam fixes the following issues:

Changes in gleam:

• Update to 1.17.0:

  • Fixed security vulnerabilities:
    • Restrict custom documentation page path and source values so gleam docs build cannot escape the docs output directory or project root (bsc#1267396, CVE-2026-32685)
    • Restrict publication tarball creation so they cannot contain files from outside the project root (bsc#1267397, CVE-2026-42795)
    • Stricter deserialisation rules for files internal the build directory to reject corrupted data (bsc#1267398, CVE-2026-43965)
  • All features and bug fixes are extensively highlighted with examples in the upstream blog post at https://gleam.run/news/single-file-gleam-beam-programs-with-escript/ and changelog at https://github.com/gleam-lang/gleam/blob/v1.17.0/CHANGELOG.md some of the highlights include:
    • Various JavaScript code generation fixes and optimization
    • Various compiler error handling improvements
    • Ability to use the todo keyword in constants
    • Improved handling of Git monorepos during package management
    • Ability to create escripts from Gleam programs
    • Various language server improvements like reference highlighting, record hovering and code actions

• Update to 1.16.0:

  • Changelog v1.16.0: https://gleam.run/news/javascript-source-maps/

• Update to 1.15.1:

  • Changelog v1.12.0: https://gleam.run/news/no-more-dependency-management-headaches/
  • Changelog v1.13.0: https://gleam.run/news/formalising-external-apis/
  • Changelog v1.14.0: https://gleam.run/news/the-happy-holidays-2025-release/
  • Changelog v1.15.0: https://gleam.run/news/upgrading-hex-security/

• Replace deprecated "disabled" mode with "manual" in _service

• Update to 1.11.0:

  • The displaying of internal types in HTML documentation has been improved
  • A warning is now emitted when the same module is imported multiple times into the same module with different aliases
  • Fixed a bug where a bit array segment matching on a floating point number would match with NaN or Infinity on the JavaScript target
  • https://github.com/gleam-lang/gleam/blob/v1.11.1/CHANGELOG.md

• Update to 1.10.0:

  • Changelog: https://gleam.run/news/global-rename-and-find-references/

• skip unit tests that requires networking upon build

• Update to 1.9.0:

  • Changelog: https://gleam.run/news/hello-echo-hello-git/

• Update to 1.8.1:

• Fixed a metadata caching bug where accessors for opaque types could sometimes be used in other modules. (Louis Pilfold)
• Changelog: https://gleam.run/news/gleam-gets-rename-variable/

• Update to 1.7.0:

• Changelog: https://gleam.run/news/improved-performance-and-publishing/

• Update to 1.6.3:

• Fixed a bug where Gleam would be unable to compile to BEAM bytecode on older versions of Erlang/OTP. (yoshi)

• Update to 1.6.2:

• Fixed a bug where patterns in use expressions would not be checked to ensure that they were exhaustive. (Surya Rose)

• Update to 1.6.1:

• fix update use_manifest logic (Jason Sipula)
• 1.6.0 Changelog: https://gleam.run/news/context-aware-compilation/