CVE-2023-22582

Executive Summary

CVE-2023-22582 is a reflected Cross-Site Scripting (XSS) vulnerability in the Danfoss AK-EM100 web application, a device used in industrial refrigeration monitoring systems. The flaw allows a remote, unauthenticated attacker to inject malicious script content into web pages served by the device, which is then executed in the context of a victim user's browser session. The Danfoss AK-EM100 has been declared End of Life (EOL), meaning no official patch will be released; organizations must rely on network-level mitigations and decommissioning efforts to address the risk.

Technical Analysis

The vulnerability is classified as a Reflected Cross-Site Scripting flaw. Reflected XSS occurs when a web application takes user-supplied input — typically via URL query parameters, form fields, or other HTTP request components — and reflects it back to the client without proper sanitization or output encoding. In the case of the Danfoss AK-EM100, the NVD description confirms that the web application reflects input in a manner that permits script execution.

Attack Mechanism: An attacker crafts a malicious URL containing JavaScript payload embedded within a parameter value. When the victim clicks the crafted link, the AK-EM100 web server processes the request, reflects the payload into the HTML response without adequate encoding, and the victim's browser executes the injected script.

Attack Surface: The attack surface is the HTTP web management interface of the AK-EM100 device, which is designed to be accessed via a web browser for configuration, monitoring, and data retrieval. An attacker requires network access to the web interface — either directly or indirectly through a phishing link — to successfully deliver the payload.

Code-Level Analysis: Insufficient technical detail is available in the NVD description to identify specific URL endpoints, parameter names, or vulnerable code paths. The vulnerability mechanism is characteristic of common XSS classes: failure to apply context-appropriate output encoding, lack of Content-Security-Policy headers, and missing input validation on reflected parameters. The device is likely running a lightweight embedded web server with minimal application-layer security controls, which is typical for Industrial Control System (ICS) devices of this era.

Notable Characteristics:

• Product is End of Life (EOL) — no firmware updates will address this flaw.
• No CISA KEV listing at the time of reporting, but EPSS percentile of 45.4% suggests moderate likelihood of eventual exploitation.
• No public PoC or exploit code confirmed at reporting time.

Exploitation Scenarios

No public PoC exists for CVE-2023-22582; the attack chain below is inferred from the vulnerability class (Reflected XSS) and standard exploitation patterns for web application flaws.

Step 1 — Reconnaissance / Target Identification: The attacker identifies internet-facing AK-EM100 devices using network scanning tools (e.g., Shodan, Censys, Masscan) with device-specific fingerprints. Indicators include the device's HTTP header banners, default page titles, or characteristic TLS certificates. Alternatively, attackers target organizations operating commercial refrigeration systems, food storage facilities, or supermarket chains — the primary deployment context of AK-EM100 hardware.

Step 2 — Crafting the Malicious Request: The attacker constructs a URL that includes a JavaScript payload in a parameter that the application reflects. For example, a generic pattern would be: https://[target-ip]/index.php?param=<script>malicious-payload</script> The exact parameter name is unknown due to insufficient detail in available intelligence; however, any reflectable input parameter in the web interface becomes a viable injection vector.

Step 3 — Payload Delivery / Execution: The attacker delivers the crafted URL to a victim via phishing email, malicious website redirect, or by planting the link in a public forum or messaging system. When the victim — likely an authorized operator or administrator of the refrigeration system — clicks the link, the AK-EM100 web server reflects the payload in the HTTP response. The victim's browser executes the malicious JavaScript in the context of the device's web origin.

Step 4 — Post-Exploitation Impact: Upon successful script execution, the attacker can perform any action that the victim's session allows, including:

• Session hijacking: Steal session cookies to authenticate as the victim.
• Credential theft: Inject keylogging or phishing overlays to capture operator credentials.
• Configuration modification: Arbitrary requests via AJAX/fetch in the victim's session context, potentially altering refrigeration setpoints, alarm thresholds, or shutdown sequences.
• Lateral movement: Use the compromised browser session as a foothold to pivot toward the ICS/OT network segment.

The severity is elevated by the fact that CVSS Base Score is 9.0, indicating critical severity, and the device's EOL status means exploitation remains viable indefinitely.

Impact Assessment

Business Impact: The Danfoss AK-EM100 is a monitoring device used in refrigeration systems — typically in food processing, cold storage, and supermarket verticals. A successful XSS exploit can lead to:

1. Operational disruption: Manipulation of refrigeration monitoring data, causing food spoilage or loss of cold-chain integrity.
2. Safety risk: Disruption of alarm systems could mask temperature excursions, creating health and safety hazards (e.g., spoiled food reaching consumers, ammonia leak undetected in industrial systems).
3. Compliance violations: Failure to maintain cold-chain compliance with regulatory bodies (e.g., FDA, HACCP) could result in fines or shutdown orders.
4. Data breach: Exfiltration of credentials and configuration data may expose network topology and device credentials usable in further attacks.

Affected Systems:

• All SKUs/firmware versions of the Danfoss AK-EM100 (End of Life).
• Fleet-wide deployment: Not officially announced, but the device was in production for years prior to EOL declaration, meaning a significant installed base potentially remains in operation.

Blast Radius: Medium — Requires a victim to click a crafted link (user interaction required, per the CVSS interaction component). However, once executed, the attacker gains access to the device's administrative interface in the victim's browser context, which can have cascading consequences for the monitored refrigeration infrastructure.

CVSS Rationale (Score: 9.0): The critical score reflects: Network attack vector (remote exploitability), Low attack complexity, No privileges required, and a Scope change (the impact spans beyond the vulnerable component itself, affecting the user's browser session and potentially connected systems). Confidentiality, Integrity, and Availability impacts are all rated High.

Detection Guidance

The following detection content targets payloads and behaviors consistent with reflected XSS exploitation against the AK-EM100 web interface. Note that since the exact vulnerable parameters are unknown, detection rules focus on generic XSS indicators and anomalous HTTP traffic to the device.

Sigma Rule

title: Danfoss AK-EM100 Reflected XSS Attempt
id: 7a2b0a5e-9d6c-43d1-b0f8-4c2e1b7c9a2d
status: experimental
description: Detects reflected XSS attempts against Danfoss AK-EM100 web interfaces by matching common script injection patterns in HTTP request URLs.
logsource:
  category: webserver
  product: generic
detection:
  selection:
    cs-method: 'GET'
    cs-uri-query|contains:
      - '<script>'
      - '%3Cscript%3E'
      - 'javascript:'
      - 'onerror='
      - 'onload='
      - 'alert('
      - 'document.cookie'
      - 'fetch('
  filter:
    cs-user-agent|contains: 'Googlebot'   # Exclude known benign scanners
  condition: selection and not filter
level: high
falsepositives:
  - Legitimate security scanners performing authorized testing
  - Developer testing inputs (unlikely in production OT environments)
tags:
  - attack.t1190
  - attack.initial-access
  - cve.2023-22582

YARA Rule

rule Danfoss_AK_EM100_Reflected_XSS
{
    meta:
        author = "Valtersit Threat Intelligence"
        description = "Matches HTTP traffic containing XSS payload patterns targeting Danfoss AK-EM100 web interface"
        reference = "CVE-2023-22582"
        date = "2024-01-15"
        severity = "critical"

    strings:
        $xss_script = /<script[\s>]/i
        $xss_js = /javascript\s*:/i
        $xss_event = /on(error|load|click|mouseover)\s*=/i
        $xss_cookie = /document\.cookie/i
        $xss_alert = /alert\s*\(/i
        $xss_fetch = /fetch\s*\(/i
        $ak_em100 = /AK-EM100/i
        $http_get = "GET "
        $http_post = "POST "

    condition:
        ($ak_em100 or filesize < 5KB) and
        (uint16(0) == 0x4854 or ($http_get at 0 or $http_post at 0)) and
        2 of ($xss_*)
}

Suricata IDS Rule

alert http any any -> any any (msg:"CVE-2023-22582 Danfoss AK-EM100 Reflected XSS Attempt"; flow:established,to_server; content:"GET "; http_method; content:"<script"; http_uri; nocase; content:"AK-EM100"; http_uri; sid:2023225821; rev:1; classtype:web-application-attack; reference:cve,2023-22582; metadata:created_at 2024_01_15, updated_at 2024_01_15;)

alert http any any -> any any (msg:"CVE-2023-22582 Danfoss AK-EM100 Reflected XSS via encoded payload"; flow:established,to_server; content:"GET "; http_method; pcre:"/\%3Cscript|javascript\:|onerror\=/i"; http_uri; sid:2023225822; rev:1; classtype:web-application-attack; reference:cve,2023-22582; metadata:created_at 2024_01_15;)

alert http any any -> any any (msg:"CVE-2023-22582 Danfoss AK-EM100 XSS - Cookie theft attempt"; flow:established,to_server; content:"document.cookie"; http_uri; content:"AK-EM100"; http_uri; sid:2023225823; rev:1; classtype:attempted-user; reference:cve,2023-22582; metadata:created_at 2024_01_15;)

Elastic Detection

// Detect refelcted XSS attempts against AK-EM100 devices
sequence by source.ip
  [ network where network.transport == "tcp" and destination.port == 80
    and url.path like "*AK-EM100*"
    and url.query like "*<script>*"
    and http.request.method == "GET" ]
  [ network where network.transport == "tcp" and destination.port == 80
    and url.query like "*document.cookie*" or url.query like "*fetch(*" ]

// Alternative standalone detection
any where network.transport == "tcp"
  and destination.port == 80
  and (url.query like "*<script>*"
       or url.query like "*%3Cscript%3E*"
       or url.query like "*javascript:*"
       or url.query like "*onerror=*"
       or url.query like "*onload=*")
  and url.path like "*AK-EM100*"

Splunk SPL Query

index=web sourcetype=access_combined
| where match(uri_path, "(?i)AK-EM100")
| where match(uri_query, "(?i)(<script>|%3Cscript%3E|javascript:|onerror=|onload=|document\.cookie|alert\()")
| table _time, src_ip, dest_ip, dest_port, method, uri_path, uri_query, http_user_agent, status
| stats count by src_ip, dest_ip, uri_path
| sort - count

Wazuh OSSEC Rule

<group name="web, xss,">

  <rule id="100822" level="12">
    <decoded_as>web</decoded_as>
    <match>AK-EM100</match>
    <description>CVE-2023-22582: Danfoss AK-EM100 web interface accessed with XSS indicators</description>
    <mitre>
      <id>T1190</id>
    </mitre>
    <group>cve-2023-22582,</group>
  </rule>

  <rule id="100823" level="14">
    <if_sid>100822</if_sid>
    <regex><script>|%3Cscript%3E|javascript:|onerror=|onload=</regex>
    <description>CVE-2023-22582: Reflected XSS payload detected in request to AK-EM100</description>
    <mitre>
      <id>T1190</id>
    </mitre>
    <group>cve-2023-22582,</group>
  </rule>

  <rule id="100824" level="8">
    <if_sid>100822</if_sid>
    <url>AK-EM100</url>
    <description>CVE-2023-22582: AK-EM100 web interface accessed</description>
    <group>cve-2023-22582,</group>
  </rule>

</group>

Mitigation & Patch Guidance

Patch confidence: 1/4 — PARTIAL (workaround/mitigation only, no official fix confirmed).

1) Immediate Mitigations (to apply now):

• Network segregation: Move all AK-EM100 devices to isolated VLANs behind firewalls with strict Access Control Lists (ACLs). Do not expose the web interface directly to the internet; place it behind a VPN or jump host.
• Restrict access: Limit administration to known, trusted IP addresses via firewall rules. Disable remote management if physical/console access is sufficient.
• Web filtering: Deploy a reverse proxy or WAF in front of AK-EM100 interfaces to block XSS payload patterns (e.g., request rules matching <script>) — note this is a compensating control and not a guarantee.
• User awareness: Instruct operators not to click links originating from email or external sources while accessing the AK-EM100 web console. Ensure they verify URL destinations before navigation.

2) Patch / Upgrade Steps:

• No vendor patch exists. The AK-EM100 is End of Life and Danfoss will not release firmware updates addressing this vulnerability.
• Decommission and replace: Danfoss advises phasing out AK-EM100. Migrate to a current, supported monitoring platform (e.g., Danfoss AK-SM800 series or newer IP-enabled controllers) that receives active security updates.
• For installations that cannot migrate immediately, continue using minimal local configuration and disconnect the device from remote access entirely.

3) Long-Term Hardening:

• Asset lifecycle management: Maintain an inventory of all OT/ICS devices with their firmware version, vendor support status, and EOL dates. Establish a replacement roadmap for EOL devices before security vulnerabilities become critical.
• Defense-in-depth: Implement network segmentation between IT and OT networks; apply ICS-specific monitoring using passive network analyzers (e.g., Zeek, Suricata) with custom rulesets for known vulnerable devices.
• Logging & auditing: Capture and review HTTP access logs from AK-EM100 devices to identify unusual query strings or unexpected administrative sessions.
• Procurement policy: Enforce security criteria (secure boot, signed firmware, central management with auth) when selecting replacement ICS equipment to prevent future EOL security gaps.

References

1. NVD Entry: https://nvd.nist.gov/vuln/detail/CVE-2023-22582 — Official CVE record with description and CVSS scoring.
2. CISA Known Exploited Vulnerabilities Catalog: https://www.cisa.gov/known-exploited-vulnerabilities-catalog — CVE-2023-22582 not currently listed; monitor this source for updates.
3. Danfoss Product End-of-Life Notice: https://www.danfoss.com/en/products/dcs/ak-em100/ — Vendor documentation confirming EOL status and migration guidance (reference advisory structure, actual URL may differ).
4. MITRE ATT&CK T1190 — Exploit Public-Facing Application: https://attack.mitre.org/techniques/T1190/ — Tactics and techniques mapping for this vulnerability's exploitation chain.
5. CWE-79 Improper Neutralization of Input During Web Page Generation: https://cwe.mitre.org/data/definitions/79.html — Weakness class underlying this vulnerability.

Threat Actor Activity / In-the-Wild Evidence: No confirmed exploitation campaigns attributed to CVE-2023-22582 exist in open-source intelligence at the time of writing. The EPSS score of 0.00598 (45.4% percentile) indicates moderate attention from the exploitation community compared to other CVEs. Given the EOL status and lack of vendor response, the likelihood of inclusion in future botnet or ICS-targeting campaigns (e.g., Mirai variants, specialized ICS exploit tools) should be considered elevated.