CVE-2026-67989Hinoki check available

Application stalls via Mistral capability regex matching

Published Oct 2, 2026 · Updated Oct 2, 2026

Regular expression denial of service in RubyLLM Mistral capability matching allows attackers to stall applications on Ruby 3.1.x. Mistral::Capabilities matches model identifiers against regular expressions whose processing can consume polynomial CPU time for crafted input. Exploitation requires an application to pass an attacker-influenced model identifier into this library code; the resulting impact is delayed or stalled application processing.

CVSS severityUnavailable
Unscored
EPSS probability0.34%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Regular expression denial of service in RubyLLM Mistral capability matching allows attackers to stall applications on Ruby 3.1.x. Mistral::Capabilities matches model identifiers against regular expressions whose processing can consume polynomial CPU time for crafted input. Exploitation requires an application to pass an attacker-influenced model identifier into this library code; the resulting impact is delayed or stalled application processing.

The record

CVE
CVE-2026-67989
Published
Oct 2, 2026
Updated
Oct 2, 2026
Vendor
Carmine Paolino
Product
RubyLLM
Classifications
T1499.004
Attack vector
Unavailable
Privileges
Unavailable

Timeline

How it unfolded

  1. Oct 2, 2026CVE publishedPublication date reported by the CVE source.
  2. Oct 2, 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?

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  1. Affected versionversion=n/a

What conditions does exploitation require?

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

What is affected?

Carmine Paolino · RubyLLMversion=n/a

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.

Activity data is delayed. The latest report is Sep 28, 2026.

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No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 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

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Technologies

Your stack

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