CVE-2026-86289: Integer Overflow in Ollama
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.
CVSS v4.0
Score 5.3medium
Affected software
Ollama
pkg:golang/github.com/ollama/ollamacpe:2.3:a:ollama:ollama:*:*:*:*:*:*:*:*Run on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
An integer overflow vulnerability was identified in the readGGUFV1String function within the GGUF Decoder component of Ollama up to version 0.31.1. This flaw allows remote attackers to cause an integer overflow via crafted input, potentially leading to unexpected behavior. The vulnerability is tracked as CVE-2026-86289 and has a CVSS 4.0 base score of 5.3 (medium severity). A patch fixing this issue was introduced in version 0.31.2-rc1, specifically in commit 67b6a1c2d45321e0cb3c04a18073f9818de7724b.
Potential Impact
The vulnerability allows remote attackers to trigger an integer overflow in the GGUF Decoder component, which may lead to application instability or other unintended effects. The CVSS score of 5.3 indicates a medium impact with no required privileges or user interaction. Although an exploit is publicly available, there are no known reports of active exploitation in the wild.
Mitigation Recommendations
Upgrade Ollama to version 0.31.2-rc1 or later, which contains the official fix for this integer overflow vulnerability. No other mitigation steps are indicated or required according to the available data.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- VulDB
- Date Reserved
- 2026-09-06T15:44:05.664Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6a9e7b6facd9273b494499ca
Added to database: 09/07/2026, 08:53:03 UTC
Last enriched: 09/14/2026, 23:41:12 UTC
Last updated: 10/21/2026, 13:20:24 UTC
Views: 147
Community Reviews
0 reviewsCrowdsource mitigation strategies, share intel context, and vote on the most helpful responses. Sign in to add your voice and help keep defenders ahead.
Want to contribute mitigation steps or threat intel context? Sign in or create an account to join the community discussion.
Actions
Updates to AI analysis require Pro Console access. Upgrade inside Console → Billing.
Need more coverage?
Upgrade to Pro Console for AI refresh and higher limits.
For incident response and remediation, OffSeq services can help resolve threats faster.
Latest Threats
Check if your credentials are on the dark web
Instant breach scanning across billions of leaked records. Free tier available.