CVE-2026-67987CWE-1333

CVE-2026-67987

High · published September 30, 2026

CVSS v3.1
7.5
EPSS
0%
Percentile
36.4
In the wild
Unconfirmed
What it is

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

The record
Technical detail
CVSS v3.1
7.5 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS v4.0
Not supplied
EPSS
0.00432 · 36.4th percentile
Weakness
CWE-1333 · Inefficient Regular Expression Complexity
Published
2026-09-30T00:17Z
References (3)
https://github.com/crmne/ruby_llm · [email protected]https://github.com/crmne/ruby_llm/blob/fa6f279847d6d7027814539d9c0dfc3bbdfd2a83/lib/ruby_llm/protocols/chat_completions/chat.rb#L355-L356 · [email protected]https://github.com/crmne/ruby_llm/commit/5e88411f171721b381853fa77d254e266dcf6ad8 · [email protected]
EPSS history
Timeline
  • 01 OCT 03:48Z
    EPSS moved — → 0%
    epss
  • 29 SEP 00:00Z
    crmne/ruby_llm at commit fa6f279847d6d7027814539d9c0dfc3bbdfd2a83 contains polynomial-time regular expression denial-of-service conditions in think-tag…
    cvelistv5