Skip to content
Fencer Intel
medium 5.9

CVE-2026-103061 json

Path traversal in Gleam via unvalidated package application names

published 28d ago modified 24d ago also EUVD-2026-97758

cvss
5.9
version 4.0, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.4%
EPSS 0.4% chance of exploitation in 30 days, percentile 34%
public exploits
0
none known

Summary

Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') vulnerability in gleam-lang gleam allows a malicious package publisher to delete a directory outside the project's build directory when a developer builds a project.

A Hex package release's metadata carries an app field with the release's OTP application name. Gleam reads this field from the hex.pm release API when it downloads dependencies and uses it as the package's build directory name without validating it (hex_manifest_package in compiler-cli/src/dependencies.rs, ProjectPaths::build_directory_for_package). When a dependency fails to compile, Gleam deletes that directory with remove_dir_all. hex.pm didn't restrict the field to a directory name before 2026-10-12, so a publisher could set it to a value such as ../../../../target or an absolute path. When a project depends on such a release directly or transitively and the release fails to compile, gleam build, gleam check, gleam run, gleam test or gleam export deletes the directory the name resolves to. For a pure Gleam package no publisher code runs.

This issue affects gleam: from 0.32.4 before 1.19.2.

Patch / fix

  • Gleam Gleam 1.19.2, v1.19.2-elixir, v1.19.2-elixir-alpine, v1.19.2-elixir-slim, v1.19.2-erlang, v1.19.2-erlang-alpine, v1.19.2-erlang-slim, v1.19.2-node, v1.19.2-node-alpine, v1.19.2-node-slim, v1.19.2-scratch
  • gleam openSUSE Tumbleweed 1.19.2-1.1

opensuse advisories openSUSE-SU-2026:12454-1

Is CVE-2026-103061 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

Check with Fencer

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-103061 updated cvss 7.1

gleam: gleam: Arbitrary directory deletion via path traversal in package metadata

  • Red Hat Enterprise Linux 8 mozjs60
    affected: workaround, no fix available
  • Red Hat Enterprise Linux 7 firefox, firefox 140.17.0-1.el10_2 Red Hat Enterprise Linux 8 firefox, thunderbird, firefox 140.17.0-1.el10_2, thunderbird 140.16.0-1.el10_2 Red Hat Enterprise Linux 9 firefox, firefox-x11, thunderbird, firefox 140.17.0-1.el10_2, thunderbird 140.16.0-1.el10_2 Red Hat Enterprise Linux 10 firefox 140.17.0-1.el10_2, thunderbird 140.16.0-1.el10_2
    not affected: component not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
24d ago

Exploit prediction

0.40% chance of exploitation in the next 30 days, higher than 34% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
CNA 4.0 5.9 CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
CNA 4.0 5.9 CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Affected products

  • Gleam Gleam

Classification

Weakness
  • CWE-22 Improper Limitation of a Pathname to a Restricted Directory

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.