Which versions of Smolagents are affected by CVE-2026-4963?

Organizations using A weakness should be aware of moderate risk from CVE-2026-4963, a code injection vulnerability rated CVSS 5.3.

Is there a public PoC exploit available for CVE-2026-4963?

Yes, a public proof-of-concept exploit is available for CVE-2026-4963. Prioritise patching immediately. EPSS: 0.0%.

How to fix or mitigate CVE-2026-4963?

Within 30 days: Identify affected systems and apply vendor patches as part of regular patch cycle. Validate input sanitization for user-controlled parameters.

Smolagents CVE-2026-4963

Q: What is the CVSS score of CVE-2026-4963?

CVE-2026-4963 has a CVSS 4.0 base score of 2.1 (Low). CVSS vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X. EPSS exploitation probability: 0.0%.

EUVD-2026-16726 LOW

Code Injection (CWE-94)

2026-03-27 VulDB

GHSA-54fq-v6x8-244g

RCE Code Injection Smolagents Hugging Face

2.1

CVSS 4.0 · NVD

Severity by source

NVD PRIMARY

2.1 LOW

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

Scope

Lifecycle Timeline

Severity Changed

Apr 29, 2026 - 01:11 NVD

MEDIUM LOW

CVSS changed

Apr 29, 2026 - 01:11 NVD

5.3 (MEDIUM) 2.1 (LOW)

PoC Detected

Mar 30, 2026 - 13:26 vuln.today

Public exploit code

EUVD ID Assigned

Mar 27, 2026 - 17:15 euvd

EUVD-2026-16726

Analysis Generated

Mar 27, 2026 - 17:15 vuln.today

CVE Published

Mar 27, 2026 - 17:05 nvd

MEDIUM 5.3

DescriptionCVE.org

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. If you want to get best quality of vulnerability data, you may have to visit VulDB.

AnalysisAI

Code injection in HuggingFace smolagents 1.25.0.dev0 allows remote attackers without authentication to execute arbitrary code through incomplete remediation of CVE-2025-9959 in the local Python executor component. The vulnerability affects the evaluate_augassign, evaluate_call, and evaluate_with functions in src/smolagents/local_python_executor.py, with publicly available exploit code and active public disclosure despite lack of vendor response.

Technical ContextAI

HuggingFace smolagents is a Python agent framework that includes a local Python code executor for evaluating expressions and function calls. The vulnerability resides in CWE-94 (Improper Control of Generation of Code, 'Code Injection'), specifically within the Python executor's expression evaluation logic. The affected functions process user-supplied input that is inadequately sanitized before execution in a Python runtime context. This represents an incomplete fix to CVE-2025-9959, indicating that initial patching efforts failed to fully eliminate the code injection pathway. The CPE affected is cpe:2.3:a:huggingface:smolagents:*:*:*:*:*:*:*:* across affected versions in the 1.25.0 development line.

RemediationAI

No vendor-released patch has been confirmed at time of analysis, as HuggingFace did not respond to early disclosure. Immediate remediation requires upgrading to a patched version once available; monitor HuggingFace repositories and security advisories at https://github.com/huggingface/smolagents for release announcements. Until a vendor patch is released, apply compensating controls: restrict network access to smolagents instances to trusted internal networks only, disable or sandbox the local Python executor component if not essential to application functionality, implement input validation and filtering on all user-supplied data passed to evaluate_augassign/evaluate_call/evaluate_with functions to block common code injection patterns, and enforce code review processes for any custom extensions to the executor. Consider temporarily migrating critical workloads to alternative agent frameworks without code injection vulnerabilities until patched versions are available.