How severe is CVE-2025-66959?

CVE-2025-66959 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2025-66959 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (90th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-66959?

CVE-2025-66959 affects Ollama. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-66959?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2025-66959 have an EU (EUVD) identifier?

Yes. CVE-2025-66959 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-3626.

When was CVE-2025-66959 published?

CVE-2025-66959 was published on 2026-01-21 and last updated on 2026-06-17.

CVE-2025-66959

CVE-2025-66959 is a high-severity vulnerability in Ollama with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 5% (90th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-3626
Weakness: CWE-20
Affected product: Ollama
Published: 2026-01-21
Last modified: 2026-06-17

Description

An issue in ollama v.0.12.10 allows a remote attacker to cause a denial of service via the GGUF decoder

Frequently asked questions

What is CVE-2025-66959?: An issue in ollama v.0.12.10 allows a remote attacker to cause a denial of service via the GGUF decoder
How severe is CVE-2025-66959?: CVE-2025-66959 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2025-66959 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (90th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-66959?: CVE-2025-66959 affects Ollama. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-66959?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2025-66959 have an EU (EUVD) identifier?: Yes. CVE-2025-66959 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-3626.
When was CVE-2025-66959 published?: CVE-2025-66959 was published on 2026-01-21 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:ollama:ollama:0.12.10:-:*:*:*:*:*:*

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