Ollama GGUF Decoder gguf.go readGGUFV1String integer overflow (CVE-2026-86289) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-86289

Ollama GGUF Decoder gguf.go readGGUFV1String integer overflow

Answer in brief

CVE-2026-86289 records a Unknown severity vulnerability in Ollama GGUF Decoder gguf.go readGGUFV1String integer overflow. The current sources do not mark it as known exploited. The current feed maps n/a/Ollama (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 7, 2026Updated Sep 7, 2026Source checked Sep 7, 2026First seen by HOL Sep 7, 2026Material review Sep 7, 2026

Upstream Advisory

Key facts

Risk: Unknown severitySource severity not reported
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Not reported

Why this deserves its current priority

A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps n/a/Ollama (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
n/a/Ollamageneric	0.31.0 \|\| 0.31.1	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for n/a/Ollama.
Review the reported fix. Monitor this advisory for an available fix and review any installs of the affected package.

Evidence timeline and material changes

Published upstream
Sep 7, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 7, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 7, 2026

Sources and claim methodology

Upstream source description

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.

Quoted source text, attributed separately from HOL analysis.