CVE-2026-108597: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') in cohere-ai cohere-python

The vulnerability in cohere-python SDK (versions 5.11.0 to 7.2.0) is a path traversal (tar slip) issue in the _s3_models_dir_to_tarfile function. It occurs because the function uses tarfile.extractall without validating archive member paths, allowing crafted tar archives containing absolute paths or '../' sequences to overwrite arbitrary files on the host system. This can be exploited by attackers who have the ability to write model archives to the victim's S3 prefix, potentially leading to arbitrary file writes on the SDK host.

Successful exploitation allows an attacker with write access to the victim's S3 prefix to overwrite arbitrary files on the host running the cohere-python SDK. This can lead to modification or corruption of critical files, potentially impacting system integrity and security. The CVSS 4.0 score is 5.9 (medium severity), reflecting the network attack vector, low attack complexity, partial privileges required, and user interaction needed.

A patch is available for this vulnerability. Users should upgrade the cohere-python SDK to a version later than 7.2.0 where this issue is fixed. Since this is a cloud-hosted service, the vendor manages remediation for the cloud environment; however, for local SDK usage, applying the official fix is necessary. Check the vendor advisory for the exact patched version and update instructions.