CVE-2026-86289Public exploitNetwork attack vector

Remote service crash via zero-length GGUF string

Published Sep 7, 2026 · Updated Sep 7, 2026

Denial of service in Ollama 0.31.0 through 0.31.1 allows remote attackers to crash the server via a crafted GGUF v1 model. readGGUFV1String accepts a zero-length string, copies no bytes, and passes -1 to bytes.Buffer.Truncate, causing a panic. Reaching the flaw requires submitting and creating an untrusted model; the crash interrupts the Ollama service without reported data disclosure.

CVSS severityUnavailable
Unscored
EPSS probability0.40%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Denial of service in Ollama 0.31.0 through 0.31.1 allows remote attackers to crash the server via a crafted GGUF v1 model. readGGUFV1String accepts a zero-length string, copies no bytes, and passes -1 to bytes.Buffer.Truncate, causing a panic. Reaching the flaw requires submitting and creating an untrusted model; the crash interrupts the Ollama service without reported data disclosure.

The record

CVE
CVE-2026-86289
Published
Sep 7, 2026
Updated
Sep 7, 2026
Vendor
Ollama
Product
Ollama
Classifications
CWE-189, CWE-190, T1499
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 7, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 7, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0.31.0
  2. Affected versionversion=0.31.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Ollama · Ollamaversion=0.31.0; version=0.31.1

Published CVSS scores

5.3VulDB CNACVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-189Numeric Errors
CWE-190Integer Overflow or Wraparound
T1499Endpoint Denial of Service

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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