7.6
HIGH CVSS 3.1
CVE-2025-9959
Sandbox escape in smolagents Local Python execution environment via dunder attributes
Description

Incomplete validation of dunder attributes allows an attacker to escape from the Local Python execution environment sandbox, enforced by smolagents. The attack requires a Prompt Injection in order to trick the agent to create malicious code.

INFO

Published Date :

Sept. 3, 2025, 5:15 p.m.

Last Modified :

Sept. 4, 2025, 3:35 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2025-9959 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 HIGH [email protected]
CVSS 3.1 HIGH MITRE-CVE
Solution
Address incomplete validation of dunder attributes to prevent sandbox escapes.
  • Validate all dunder attributes rigorously.
  • Prevent prompt injection attacks.
  • Update smolagents to the latest version.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2025-9959.

URL Resource
https://github.com/huggingface/smolagents/pull/1551
https://research.jfrog.com/vulnerabilities/smolagents-local-python-sandbox-escape-jfsa-2025-001434277/
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2025-9959 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2025-9959 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2025-9959 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2025-9959 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Sep. 03, 2025

    Action Type Old Value New Value
    Added Description Incomplete validation of dunder attributes allows an attacker to escape from the Local Python execution environment sandbox, enforced by smolagents. The attack requires a Prompt Injection in order to trick the agent to create malicious code.
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:H/A:L
    Added CWE CWE-94
    Added Reference https://github.com/huggingface/smolagents/pull/1551
    Added Reference https://research.jfrog.com/vulnerabilities/smolagents-local-python-sandbox-escape-jfsa-2025-001434277/
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
Vulnerability Scoring Details
Base CVSS Score: 7.6
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality Impact
Integrity Impact
Availability Impact