CVE-2026-109153

6.3Medium

Published 13 Oct 2026 · NVD status: Deferred · AI triage by gemini-3.8-flash

6.3Medium

Attack vector: Network
Complexity: Low
Privileges needed: None
User interaction: Required
Impact: Limited impact
Weakness: CWE-22

Impact

Remote attackers can overwrite or create arbitrary files on the local system by getting a user or process to extract a malicious checkpoint archive. This can lead to code execution or service disruption depending on what gets overwritten.

Root cause

The checkpoint extraction code calls tarball.extractall without validating destination paths, enabling directory traversal via archive member filenames.

Affected systems

MosaicML Composer up to 0.32.1

CVSS v3.1 · CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L

Fix & remediation

Upgrade MosaicML Composer to a version newer than 0.32.1 when available. As an interim workaround, avoid downloading or extracting checkpoints from untrusted or public sources.

shell

$ pip list | grep composer

AI-suggested. Run it in staging first and check it against the vendor advisory. Why?

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NVD description

A vulnerability was detected in MosaicML Composer up to 0.32.1. This affects the function tarball.extractall of the file composer/utils/checkpoint.py of the component Checkpoint Extraction. The manipulation results in path traversal. The attack can be executed remotely. The vendor was contacted early about this disclosure.

References

Source: nvd.nist.gov/vuln/detail/CVE-2026-109153