CVE-2026-81838 - Zip Slip path traversal in awsdac (diagram-as-code)

Imported from official source

Security notice

Cybersecurity Classified by Officially

CVE-2026-81838 - Zip Slip path traversal in awsdac (diagram-as-code)

Bulletin ID: 2026-090-AWS
Scope: AWS
Content Type: Important (requires attention)
Publication Date: 08/27/2026 13:00 PM PDT
Last Updated: 08/28/2026 09:30 AM PDT

awsdac (diagram-as-code) is a CLI tool that generates AWS architecture diagrams from YAML definitions, enabling version-controlled, code-driven diagramming. We identified CVE-2026-81838, a Zip Slip (path traversal) issue. When awsdac extracts a zip archive referenced by a ZipFile resource in a definition file, a crafted archive can write files outside the intended cache directory, to any path writable by the user running awsdac. Depending on the file written, this can lead to arbitrary code execution.

Leveraging this issue requires processing a definition file from an untrusted source. This can occur when:

  • awsdac is run without definition trust restrictions (versions prior to 0.22.4 had no trust distinction; version 0.22.4 and later require the --allow-untrusted-definitions flag), or
  • a definition file is loaded from the local filesystem (`Type: LocalFile`), which bypasses the definition URL allowlist.
  • CI/CD environments that process definition files from untrusted or semi-trusted sources are the primary risk scenario.

    awsdac is a client-side CLI tool that renders architecture diagrams locally. This issue does not affect any AWS service, AWS account, or customer data. The impact is limited to the machine on which awsdac runs.

    Impacted versions: awsdac: versions 0.10 through 0.23 (inclusive)

    This issue has been addressed in version 0.24. We recommend upgrading to the latest version and ensuring any forked or derivative code is patched to incorporate the new fixes.

  • Only process definition files (including local files) from sources you trust.
  • Do not run awsdac with the --allow-untrusted-definitions flag (version 0.22.4 and later).
  • In CI/CD pipelines, pin the definition files consumed by awsdac to reviewed, trusted content.
  • This is an extract. The publication continues at the source.

    Read the original at the source: https://aws.amazon.com/security/security-bulletins/rss/2026-090-aws/

    Officially imported this from Amazon Web Services’s own source and shows an extract. If you work there, claiming the profile and verifying the domain lets you choose to show the full text here.

    This publication has changed since it was first published

    3 versions recorded. The original is kept in full — nothing is overwritten.

    1. v3 imported change on current
    2. v2 imported change on
    3. v1 as first published on

    Provenance

    Organization
    Amazon Web Services — imported from official source
    Official source
    https://aws.amazon.com/security/security-bulletins/feed/ RSS
    Imported
    September 15, 2026 20:57
    Versions
    3 recorded
    Identity
    fc72305d6fa73928de5a5278d918b06c5ee71268

    Officially records where a publication came from, not whether it is true. Imported records are reproduced from an organization's own official source.