CVE-2026-67987
Received
Received - Intake
Regular Expression DoS in ruby_llm via Think-Tag Parsing
Vulnerability report for CVE-2026-67987, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-09-29
Last updated on: 2026-09-29
Assigner: MITRE
Description
Description
crmne/ruby_llm at commit fa6f279847d6d7027814539d9c0dfc3bbdfd2a83 contains polynomial-time regular expression denial-of-service conditions in think-tag response parsing on Ruby 3.1.x. A malicious or anomalous model response containing many unterminated <think> tags can cause excessive CPU consumption in two consecutive regular expressions and delay chat-completion processing
CVSS Scores
EPSS Scores
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| Percentile: |
Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| crmne | ruby_llm | From 3.1.0 (inc) to 3.1.9 (inc) |
| crmne | ruby_llm | From 3.1.0 (inc) to 3.2.0 (exc) |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-UNKNOWN |
