RCE in Huggingface Smolagents

CVE-2026-4963

A weakness has been identified in huggingface smolagents 1.25.0.dev0. This affects the function evaluate_augassign/evaluate_call/evaluate_with of the file src/smolagents/local_python_executor.py of the component Incomplete Fix CVE-2025-9959. This manipulation causes code injection. It is possible to initiate the attack remotely. The exploit has been made available to the public and could be used for attacks. The vendor was contacted early about this disclosure but did not respond in any way.

EPSS: 0.006 (45.3th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L.

Affected products

Weakness classification (CWE)

References

  • cna@vuldb.com (technical-description, VDB Entry, Third Party Advisory, vdb-entry)
  • cna@vuldb.com (signature, Permissions Required, permissions-required, VDB Entry)
  • cna@vuldb.com (Exploit, VDB Entry, Third Party Advisory, third-party-advisory)
  • cna@vuldb.com (Exploit, VDB Entry, Third Party Advisory, third-party-advisory)
  • cna@vuldb.com (Exploit, VDB Entry, Third Party Advisory, third-party-advisory)
  • cna@vuldb.com (related, Exploit, Third Party Advisory)
  • cna@vuldb.com (Exploit, Third Party Advisory, exploit)

Frequently asked questions

What is CVE-2026-4963?
CVE-2026-4963 is a medium-severity vulnerability in Huggingface Smolagents, classified under Improper Neutralization of Special Elements in Output Used by a Downstream Component (Injection). CVSS score: 6.3/10. Published 2026-03-27.
How severe is CVE-2026-4963?
Medium severity. CVSS v3 base score is 6.3 out of 10.