CVE-2026-31239CWE-502insecure-deserialization

CVE-2026-31239

Critical · published May 12, 2026

CVSS v3.1
9.8
EPSS
1%
Percentile
47.9
In the wild
Unconfirmed
What it is

The mamba language model framework thru 2.2.6 is vulnerable to insecure deserialization (CWE-502) when loading pre-trained models from HuggingFace Hub. The MambaLMHeadModel.from_pretrained() method uses torch.load() to load the pytorch_model.bin weight file without enabling the security-restrictive weights_only=True parameter. This allows the deserialization of arbitrary Python objects via the pickle module. An attacker can exploit this by publishing a malicious model repository on HuggingFace Hub. When a victim loads a model from this repository, arbitrary code is executed on the victim's system in the context of the mamba process.

The record
Technical detail
CVSS v3.1
9.8 · CRITICAL
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS v4.0
Not supplied
EPSS
0.00597 · 47.9th percentile
Weakness
CWE-502 · Deserialization of Untrusted Data
Published
2026-05-12T22:16Z
References (2)
EPSS history
Timeline
  • 12 MAY 00:00Z
    The mamba language model framework thru 2.2.6 is vulnerable to insecure deserialization (CWE-502) when loading pre-trained models from HuggingFace Hub
    cvelistv5