Sandbox escape in smolagents Local Python execution environment via dunder attributes
Priority LOW 33CWE-94Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- Required
- Attack complexity
- Low
- Impact type
- Code execution
- Confidentiality · integrity · availability
- Low · High · Low
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-94.
Summary
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.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00312 24th percentileScored 2026-11-07
Fix Fixed smolagents: 1.21.0
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | smolagents | before 1.21.0 | 1.21.0 | Patch available | CNA |
- smolagents Vendor— Affected before 1.21.0 Fixed in 1.21.0 Patch available CNA
Remediation
- Fix · CNA smolagents Fixed in 1.21.0
Timeline
- 2026-10-02 Threatist record created from CVE-2025-9959
- 2026-10-03 Alias added: GHSA-p8v6-48p4-f4r4
References
Sources
- CVE-2025-9959 · CVE Program
- CVE-2025-9959 · NVD
- FIRST EPSS
- GHSA-p8v6-48p4-f4r4 · GitHub Advisory Database · CC BY 4.0
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