CVE-2026-67211Hinoki check available

JVM crash via unbounded SymSpell map pre-sizing

Published Sep 11, 2026 · Updated Sep 11, 2026

Denial of service in Apache OpenNLP 3.0.0-M4 through 3.0.0-M5 allows attackers to crash a JVM via a crafted SymSpell model. SymSpellModelSerializer.create() passes attacker-controlled unigram or bigram counts directly to LinkedHashMap pre-sizing without an upper bound, causing a multi-gigabyte allocation and OutOfMemoryError. Exploitation requires an application or command-line process to load a SymSpell model from an untrusted or semi-trusted source, and the resulting impact is a process crash.

CVSS severityUnavailable
Unscored
EPSS probability0.32%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Denial of service in Apache OpenNLP 3.0.0-M4 through 3.0.0-M5 allows attackers to crash a JVM via a crafted SymSpell model. SymSpellModelSerializer.create() passes attacker-controlled unigram or bigram counts directly to LinkedHashMap pre-sizing without an upper bound, causing a multi-gigabyte allocation and OutOfMemoryError. Exploitation requires an application or command-line process to load a SymSpell model from an untrusted or semi-trusted source, and the resulting impact is a process crash.

The record

CVE
CVE-2026-67211
Published
Sep 11, 2026
Updated
Sep 11, 2026
Vendor
The Apache Software Foundation
Product
Apache OpenNLP
Classifications
T1499.004
Attack vector
Unavailable
Privileges
Unavailable

Timeline

How it unfolded

  1. Sep 11, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 11, 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=3.0.0-M4 <3.0.0-M6

What conditions does exploitation require?

Attack vectorUnavailable in this record.
Required privilegesUnavailable in this record.

What is affected?

The Apache Software Foundation · Apache OpenNLPversion=3.0.0-M4 <3.0.0-M6

Published CVSS scores

No CVSS assessment is available in this record.

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)
VectorUnavailable
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

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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