CVE-2026-8258 — Squirrel Buffer Overflow

title: Local Privilege Escalation via Squirrel Buffer Overflow - CVE-2026-8258
id: scw-2026-05-11-ai-1
status: experimental
level: critical
description: |
  Detects the execution of the Squirrel binary with command line arguments that suggest an attempt to exploit the validate_format function in sqstdlib/sqstdstring.cpp, leading to a stack-based buffer overflow (CVE-2026-8258). This is a critical local privilege escalation vulnerability.
author: SCW Feed Engine (AI-generated)
date: 2026-05-11
references:
  - https://shimiscyberworld.com/posts/nvd-CVE-2026-8258/
tags:
  - attack.privilege_escalation
  - attack.t1068
logsource:
    category: process_creation
detection:
  selection:
      Image|endswith:
          - 'squirrel.exe'
      CommandLine|contains:
          - 'sqstdstring.cpp'
      condition: selection
falsepositives:
  - Legitimate administrative activity

Source: Shimi's Cyber World · License & reuse