RCE in Project-Monai Monai
CVE-2026-100842
MONAI through 1.6.0 contains an eval injection vulnerability in _get_fake_spatial_shape() in monai/bundle/scripts.py. The function validates shape expressions with a helper that walks the AST and only collects ast.Name nodes, rejecting any name other than 'p' or 'n', before passing the string to eval(). Expressions built solely from constants and attribute, subscript, or call nodes (for example "(1).__class__.__bases__[0].__subclasses__()" or "int.__class__.__init__.__globals__") contain no ast.Name nodes and therefore bypass the allowlist. Because the shape value originates from bundle metadata consumed by _get_real_input_data and verify_net_in_out (reachable through the bundle 'verify_net_in_out' CLI flow), an attacker who can influence a bundle's metadata can escape the eval sandbox via object introspection chains and achieve code execution in this non-default flow.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.0 (High). Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.002 (8.0th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 8th percentile — 8.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.001 · newest: 0.002 · change: +0.000
Affected products
Weakness classification (CWE)
References
- GitHub Security Advisory (GHSA-h89g-r5pc-wxfm) (vendor-advisory, Exploit, Mitigation, Vendor Advisory)
- VulnCheck Advisory: MONAI through 1.6.0 _get_fake_spatial_shape eval() Sandbox Bypass via Attribute Chains (Third Party Advisory, third-party-advisory)
Frequently asked questions
- What is CVE-2026-100842?
- CVE-2026-100842 is a high-severity vulnerability in Project-Monai Monai, classified under Eval Injection. CVSS score: 7.0/10. Published 2026-09-27.
- How severe is CVE-2026-100842?
- High severity. CVSS v3 base score is 7.0 out of 10.