CVE-2026-67987

State: Published
Severity: 7.5 High
Published: Sep 29, 2026
Updated: Oct 1, 2026
Reserved: Jul 30, 2026

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

Scores

CVSS	Score	Vector	Source
3.1	7.5 High	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H	CISA-ADP

Weaknesses

CWE-1333 Inefficient Regular Expression Complexity

Affected Products

Product	Versions
n/an/a	n/aAffected

References

https://github.com/crmne/ruby_llm
https://github.com/crmne/ruby_llm/blob/fa6f279847d6d7027814539d9c0dfc3bbdfd2a83/lib/ruby_llm/protocols/chat_completions/chat.rb#L355-L356
https://github.com/crmne/ruby_llm/commit/5e88411f171721b381853fa77d254e266dcf6ad8

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