CVE-2025-66959 Denial of service in n/a
A remote attacker can cause a denial of service in Ollama via the GGUF decoder, affecting LLM server availability.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2025-66959?
CVE-2025-66959 is a high-severity denial of service vulnerability in n/a, published on 21 Jan 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
An issue in ollama v.0.12.10 allows a remote attacker to cause a denial of service via the GGUF decoder
Which versions are affected by CVE-2025-66959?
It affects 1 product.
Products include Ollama Ollama.
How do I fix CVE-2025-66959?
Upgrade to a fixed version.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2025-66959 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-66959 exists.
Other vulnerabilities in n/a
- CVE-2025-63389 Ollama Platform has missing authentication enabling attackers to perform model management operations
- CVE-2024-45436 Ollama can extract members of a ZIP archive outside of the parent directory
- CVE-2026-7482 Ollama heap out-of-bounds read in GGUF tensor parsing leaks server process memory to unauthenticated remote attackers
- CVE-2024-37032 Ollama does not validate the format of the digest (sha256 with 64 hex digits)
- CVE-2025-15514 Ollama Multi-Modal Model Image Processing NULL Pointer Dereference
Sources
Also known as GHSA-h73v-mc67-xw25, MINI-vj8p-hx49-g82g.