CVE-2026-67991: n/a
crmne/ruby_llm at commit fa6f279847d6d7027814539d9c0dfc3bbdfd2a83 contains a polynomial-time regular expression denial-of-service condition in RubyLLM::Utils.underscore on Ruby 3.1.x. A very long crafted class, agent, or tool name can cause excessive CPU consumption and a denial of service.
AI Analysis
Technical Summary
The vulnerability exists in the crmne/ruby_llm repository at commit fa6f279847d6d7027814539d9c0dfc3bbdfd2a83, specifically in the RubyLLM::Utils.underscore method when running on Ruby 3.1.x. The method uses a regular expression that exhibits polynomial-time complexity, which can be exploited by an attacker supplying a very long crafted string (class, agent, or tool name). This causes excessive CPU usage, resulting in a denial-of-service condition.
Potential Impact
Successful exploitation leads to denial of service due to excessive CPU consumption caused by the vulnerable regular expression. This impacts availability of the affected application or service running Ruby 3.1.x with the vulnerable code. There is no indication of data breach or code execution.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or workaround is currently documented. Users should monitor vendor communications for updates and consider limiting input length or sanitizing inputs as a temporary measure.
CVE-2026-67991: n/a
Description
crmne/ruby_llm at commit fa6f279847d6d7027814539d9c0dfc3bbdfd2a83 contains a polynomial-time regular expression denial-of-service condition in RubyLLM::Utils.underscore on Ruby 3.1.x. A very long crafted class, agent, or tool name can cause excessive CPU consumption and a denial of service.
CVSS v3.1
Score 7.5high
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability exists in the crmne/ruby_llm repository at commit fa6f279847d6d7027814539d9c0dfc3bbdfd2a83, specifically in the RubyLLM::Utils.underscore method when running on Ruby 3.1.x. The method uses a regular expression that exhibits polynomial-time complexity, which can be exploited by an attacker supplying a very long crafted string (class, agent, or tool name). This causes excessive CPU usage, resulting in a denial-of-service condition.
Potential Impact
Successful exploitation leads to denial of service due to excessive CPU consumption caused by the vulnerable regular expression. This impacts availability of the affected application or service running Ruby 3.1.x with the vulnerable code. There is no indication of data breach or code execution.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or workaround is currently documented. Users should monitor vendor communications for updates and consider limiting input length or sanitizing inputs as a temporary measure.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mitre
- Date Reserved
- 2026-07-30T00:00:00.000Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a7dcd46bf8831d5394706f8
Added to database: 08/13/2026, 13:57:26 UTC
Last enriched: 08/13/2026, 14:13:38 UTC
Last updated: 08/13/2026, 17:54:46 UTC
Views: 4
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