CVE-2026-118684: MONAI before 1.6.1 Missing Integrity Verification via check_hash in Downloads
MONAI before 1.6.1 contains an insufficient integrity verification vulnerability in checkhash() that silently returns True when hashval is None, with MD5 as the default hash type. Attackers performing man-in-the-middle or registry compromise can substitute bundles, datasets, or model archives downloaded without hashes, enabling malicious file delivery and potential code execution.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
MONAIto a version that resolves this vulnerability.Fixed in 1.6.1
Event History
Frequently Asked Questions
Which deployments are exposed?
Deployments using MONAI versions before 1.6.1 are exposed when they download bundles, datasets, or model archives without supplying a hash value for integrity verification.
What does an attacker need to exploit this issue?
An attacker needs the ability to substitute a downloaded file, such as through a man-in-the-middle position or compromise of the relevant registry. No authentication or user interaction is required according to the provided vector.
How can I determine whether a download is affected?
Review MONAI download workflows for calls to check_hash() where hash_val is None or where no hash is provided for the downloaded bundle, dataset, or model archive. In that condition, check_hash() silently returns True.
What should be done if upgrading is not immediately possible?
Provide and verify a hash for every downloaded artifact rather than allowing hash_val to be None. Avoid relying on the default MD5 hash type where stronger integrity verification is available.