CVE-2025-14931: Hugging Face smolagents: Unsafe deserialization in Remote Python Executor leads to RCE

Should you act?

Critical and remotely reachable

No known exploitation yet, but it is network-reachable without credentials. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.

• No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
• EPSS 1.1%, percentile 65: FIRST’s model estimates a 1.1% chance of exploitation activity in the next 30 days, higher than 65% of all scored CVEs (moderate). EPSS is a probability, not a verdict.
• Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
• Only applies if your dependency tree includes smolagents (PyPI) <= 1.23.0, no fixed version listed. Check your lockfile, including transitive dependencies.

What it is

Hugging Face smolagents Remote Python Executor Deserialization of Untrusted Data Remote Code Execution Vulnerability. This vulnerability allows remote attackers to execute arbitrary code on affected installations of Hugging Face smolagents. Authentication is not required to exploit this vulnerability. The specific flaw exists within the parsing of pickle data. The issue results from the lack of proper validation of user-supplied data, which can result in deserialization of untrusted data. An attacker can leverage this vulnerability to execute code in the context of the service account. Was ZDI-CAN-28312.

From the GitHub advisory

Hugging Face smolagents Remote Python Executor Deserialization of Untrusted Data Remote Code Execution Vulnerability. This vulnerability allows remote attackers to execute arbitrary code on affected installations of Hugging Face smolagents. Authentication is not required to exploit this vulnerability.

The specific flaw exists within the parsing of pickle data. The issue results from the lack of proper validation of user-supplied data, which can result in deserialization of untrusted data. An attacker can leverage this vulnerability to execute code in the context of the service account. Was ZDI-CAN-28312.

Weakness type: CWE-502.

Product: smolagents (PyPI) · Assigned by: zdi · Published: 2025-12-23

Affected and fixed versions

Severity scores

• Attack vector: network (remotely reachable)
• Attack complexity: low
• Privileges required: none (no login)
• User interaction: none
• Scope: changed (can affect other components)

CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.

Exploitation and urgency

• CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
• CISA SSVC assessment: exploitation none, automatable yes, technical impact total.
• FIRST EPSS (model of 2026-10-21): 1.09% probability of exploitation activity in the next 30 days; percentile 65.

Timeline

• 2025-12-23 — CVE record published by zdi
• 2025-12-23 — GitHub-reviewed advisory GHSA-q9r5-6hrr-9ph7 published (critical)
• 2025-12-26 — CVE record last updated

Sources and references

Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.

Vulnerability records

1. GitHub Advisory GHSA-q9r5-6hrr-9ph7 github.com
2. CVE.org record CVE-2025-14931 cve.org
3. NVD entry CVE-2025-14931 nvd.nist.gov

Other references from the CVE record and advisory

1. ZDI-25-1143 zerodayinitiative.com

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