CVE-2026-93348: Unsloth Zoo Code Injection via model_type in config.json

Severity: high (CVSS 8.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-09-28 · updated 2026-09-30
Weakness: CWE-94

Description

Unsloth Zoo versions 2025.9.9 before 2026.8.14, as implemented in Unsloth 2025.9.9 through 2026.8.19, contains a code injection vulnerability in the model-loading compile path where the get_transformers_model_type() function in hf_utils.py collects model_type values from nested model configurations without enforcing a character allowlist, allowing newlines and arbitrary Python source to survive normalization. Attackers can embed a newline in a nested model_type value within a malicious model's config.json to terminate the generated import statement and execute arbitrary Python code via exec() in unsloth_compile_transformers(), achieving remote code execution as the loading user when the model is loaded for training or inference.

Affected products

unslothai unsloth: from 2025.9.9 before 2026.8.20 — fixed in 2026.8.20
unslothai unsloth-zoo: from 2025.9.9 before 2026.8.14 — fixed in 2026.8.14

How to fix

Upgrade to a fixed version: unslothai unsloth 2026.8.20; unslothai unsloth-zoo 2026.8.14. Check the vendor advisory for mitigations.

References

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