AWS ParallelCluster 3.16.0 Fixes Log Export Path Traversal

P2 — VALIDATE AND UPDATEModerate (project severity) · 6.4 (project CVSS v3.1 base score)EXPLOITATION: NOT STATED

Quick Answer

Update ParallelCluster CLI hosts and runners to 3.16.0 or later. Restrict writers to the log-export bucket, review unexpected local files after exports, and validate normal exports with the patched CLI.

Confirm Scope And Apply The Supported Remediation

What to do now: Record CLI versions, export commands, workstation and runner identities, destination directories and S3 write permissions. Confirm whether untrusted principals could write export objects and learn a task ID while a vulnerable CLI exported logs. Upgrade aws-parallelcluster to 3.16.0 or later and incorporate the fix into maintained forks. Limit export-bucket access to trusted principals. Confirm the active CLI package on each host, run a representative authorized export, review unexpected files outside the export directory and retain access-policy and package evidence.

Open the authoritative advisory

Last verified: 2026-11-10 UTC. Recheck the authoritative advisory and supported distribution channel before changing production.

Scope And Authority

Product scopeAWS ParallelCluster CLI log export commands
Advisory2026-174-AWS / GHSA-h79v-mp93-644r
CVECVE-2026-124033
Authoritative release dateNovember 9, 2026 at 13:00 PST (21:00 UTC), from AWS bulletin 2026-174-AWS.
Authority revision dateNo later revision stated.
Affected versionsaws-parallelcluster 3.0.0 through versions before 3.16.0 when export-cluster-logs or export-image-logs consumes attacker-controlled S3 objects. The attacker requires write access to the export bucket and knowledge of the export task ID.
Fixed versionaws-parallelcluster 3.16.0 or later
CVSS base score6.4 (project CVSS v3.1 base score)
CVSS severityModerate (project severity)
Exploitation statusAWS does not state exploitation in the bulletin or project advisory.; no exploitation claim is inferred.

What Changed

AWS fixed relative path traversal in the ParallelCluster log export commands. Crafted S3 object names can cause writes outside the intended directory, with the exporting user’s permissions; the project does not describe a file-read capability.

What To Validate Now

  1. Inventory. Record CLI versions, export commands, workstation and runner identities, destination directories and S3 write permissions.
  2. Establish applicability. Confirm whether untrusted principals could write export objects and learn a task ID while a vulnerable CLI exported logs.
  3. Remediate. Upgrade aws-parallelcluster to 3.16.0 or later and incorporate the fix into maintained forks. Limit export-bucket access to trusted principals.
  4. Validate. Confirm the active CLI package on each host, run a representative authorized export, review unexpected files outside the export directory and retain access-policy and package evidence.
  5. Retain evidence. Preserve asset and owner identifiers, the applicability decision, before-and-after versions, change approval, installation output, validation results, and any exception or rollback record.

Operational Cautions

A successful export does not prove earlier exports were safe. Preserve local artifacts and S3 audit history before cleanup; do not broaden bucket permissions to troubleshoot an update.

Evidence To Retain

  • Exact product, release stream, package or application version, enabled feature, environment, and accountable owner.
  • UTC timestamps, authority revision, approved change record, installer or package-manager output, and resulting version.
  • Relevant logs and monitoring evidence, test results, exceptions, compensating controls, and rollback decisions.

Related TechGeeks Resources

Authoritative References

Correction policy: If the authority changes affected versions, fixed versions, severity, exploitation information, mitigations, or required action, TechGeeks will update this notice and its verification date.