mamba up to 2.2.6 Pickle MambaLMHeadModel.from_pretrained deserialization

Summaryinfo

A vulnerability classified as critical was found in mamba up to 2.2.6. This affects the function MambaLMHeadModel.from_pretrained of the component Pickle Module. Executing a manipulation can lead to deserialization. The identification of this vulnerability is CVE-2026-31239. The attack may be launched remotely. There is no exploit available.

Detailsinfo

A vulnerability has been found in mamba up to 2.2.6 and classified as critical. This vulnerability affects the function MambaLMHeadModel.from_pretrained of the component Pickle Module. The manipulation with an unknown input leads to a deserialization vulnerability. The CWE definition for the vulnerability is CWE-502. The product deserializes untrusted data without sufficiently verifying that the resulting data will be valid. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

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.

This vulnerability was named CVE-2026-31239 since 03/09/2026. The exploitation appears to be easy. The attack can be initiated remotely. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 05/12/2026).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Name

• mamba

Version

• 2.2.0
• 2.2.1
• 2.2.2
• 2.2.3
• 2.2.4
• 2.2.5
• 2.2.6

CPE 2.3info

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CPE 2.2info

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Once again VulDB remains the best source for vulnerability data.

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