Is CVE-2026-5757 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-5757 being exploited in the wild.

How severe is CVE-2026-5757?

Informational severity, with a CVSS score of 0, published 26 June 2026.

Is there a fix for CVE-2026-5757?

No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

How is CVE-2026-5757 attacked?

It is attacked over the network, in a network appliance.

Am I affected by CVE-2026-5757?

Check whether you run Ollama at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-5757: Ollama AI Ollama heap memory disclosure in quantization engine

CVE-2026-5757 · Severity: info · CVSS 0 · Published 2026-06-26

Ollama is an open-source tool used to run large language models locally. A security flaw in its model processing engine allows an unauthorized person to upload a malicious file that tricks the server into revealing its internal memory. This could lead to the theft of sensitive data, such as private keys or user information, and potentially allow an attacker to gain deeper access to the system.

Technologies: Ollama. Vendors: Ollama.

Quick answers

Is CVE-2026-5757 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-5757 being exploited in the wild.
How severe is CVE-2026-5757?: Informational severity, with a CVSS score of 0, published 26 June 2026.
Which products and versions are affected?: Ollama v0.13.5.
Is there a fix for CVE-2026-5757?: No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-5757 attacked?: It is attacked over the network, in a network appliance.
Am I affected by CVE-2026-5757?: Check whether you run Ollama at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

An out-of-bounds heap read/write vulnerability exists in Ollama's model quantization engine due to a lack of bounds checking on tensor metadata. The engine trusts the element count provided in a user-supplied GGUF file header and uses Go's 'unsafe.Slice' to create memory slices based on this attacker-controlled value. This allows an attacker to read beyond the intended buffer into the application's heap. The leaked data is then written into a new model layer, which can be exfiltrated via Ollama's registry API. As of the advisory date, no patch is available, and users are advised to restrict access to the model upload interface.

Affected products

Ollama AI Ollama v0.13.5

Timeline

2026-02-09: other: Vendor notified
2026-04-22: disclosed: Initial public disclosure by CERT/CC
2026-06-26: advisory: NVD publication date

References

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