Integer overflow in Ollama
CVE-2026-86289
A vulnerability was found in Ollama up to 0.31.1. This issue affects the function readGGUFV1String of the file fs/ggml/gguf.go of the component GGUF Decoder. Performing a manipulation results in integer overflow. The attack is possible to be carried out remotely. The exploit has been made public and could be used. Upgrading to version 0.31.2-rc1 is capable of addressing this issue. The patch is named 67b6a1c2d45321e0cb3c04a18073f9818de7724b. It is recommended to upgrade the affected component.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 4.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L.
EPSS exploit prediction
EPSS: 0.007 (52.1th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 52nd percentile — 52.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.007 · change: +0.003
Affected products
- Ollama — versions 0.31.0, 0.31.1
Weakness classification (CWE)
References
- vuldb.com/vuln/399448 (technical-description, vdb-entry)
- vuldb.com/vuln/399448/cti (signature, permissions-required)
- vuldb.com/cve/CVE-2026-86289 (third-party-advisory)
- vuldb.com/submit/906136 (third-party-advisory)
- github.com/ollama/ollama/issues/17033 (issue-tracking, exploit)
- github.com/ollama/ollama/pull/17062 (issue-tracking, patch)
- github.com/ollama/ollama/commit/67b6a1c2d45321e0cb3c04a18073f9818de7724b (patch)
- github.com/ollama/ollama/releases/tag/v0.31.2-rc1 (patch)
- github.com/ollama/ollama/ (product)
Frequently asked questions
- What is CVE-2026-86289?
- CVE-2026-86289 is a medium-severity vulnerability in Ollama, classified under CWE-189. CVSS score: 4.3/10. Published 2026-09-07.
- How severe is CVE-2026-86289?
- Medium severity. CVSS v3 base score is 4.3 out of 10.