CVE-2026-6521 — Denial of Service
CVE-2026-6521 — OpenFlow v5 protocol dissector infinite loops in Wireshark 4.6.0 to 4.6.4 and 4.4.0 to 4.4.14 allows denial of service
What This Means For You
- If your environment is affected by CWE-835, review your exposure and prioritize patching based on your environment. Monitor vendor advisories for CVE-2026-6521 updates and patches.
Related ATT&CK Techniques
🛡️ Detection Rules
1 rule · 6 SIEM formats1 detection rule auto-generated for this incident, mapped to MITRE ATT&CK. Sigma YAML is free — export to any SIEM format via the Intel Bot.
Potential Wireshark OpenFlow Dissector DoS Attempt - CVE-2026-6521
title: Potential Wireshark OpenFlow Dissector DoS Attempt - CVE-2026-6521
id: scw-2026-04-30-ai-1
status: experimental
level: high
description: |
This rule detects the execution of Wireshark with command-line arguments that suggest an attempt to process the OpenFlow protocol. This is specific to CVE-2026-6521, which involves an infinite loop vulnerability in the OpenFlow dissector of Wireshark versions 4.6.0-4.6.4 and 4.4.0-4.4.14, leading to a denial of service.
author: SCW Feed Engine (AI-generated)
date: 2026-04-30
references:
- https://shimiscyberworld.com/posts/nvd-CVE-2026-6521/
tags:
- attack.impact
- attack.t1499
logsource:
category: process_creation
detection:
selection:
Image|endswith:
- 'wireshark.exe'
CommandLine|contains:
- 'openflow'
condition: selection
falsepositives:
- Legitimate administrative activity
Source: Shimi's Cyber World · License & reuse
Indicators of Compromise
| ID | Type | Indicator |
|---|---|---|
| CVE-2026-6521 | vulnerability | CVE-2026-6521 |
| CWE-835 | weakness | CWE-835 |
Written by SCW Vulnerability Desk
Source & Attribution
| Source Platform | NVD |
| Channel | National Vulnerability Database |
| Published | April 30, 2026 at 10:16 UTC |
This content was curated and summarized by Shimi's Cyber World for informational purposes. It is not copied or republished in full. All intellectual property rights remain with the original author and source.
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