CVE-2026-65124

Executive Summary

CVE-2026-65124 is an XML injection vulnerability (CWE-91) in NVIDIA Infrastructure Controller for Linux, where an authenticated attacker with network access could inject malicious XML content, potentially leading to data tampering and denial of service. The vulnerability carries a CVSS 3.1 base score of 5.9 (Medium severity) with a vector of AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:H/A:H, reflecting high complexity and high privilege requirements but significant integrity and availability impact. No public exploit code, PoC, or Nuclei template is currently available, and no patch has been confirmed from any tracked source, leaving affected deployments without a vendor-supplied fix at this time.

Technical Analysis

CVE-2026-65124 is classified under CWE-91: XML Injection (also known as Blind XPath Injection or XML External Entity injection in some contexts, though CWE-91 specifically denotes XML Injection where improperly sanitized user input is inserted into XML documents or queries). The vulnerability resides in NVIDIA Infrastructure Controller for Linux, a product used for infrastructure management and orchestration in data center environments.

The NVD description states: "NVIDIA Infrastructure Controller for Linux contains a vulnerability where an attacker could cause an XML injection. A successful exploit of this vulnerability might lead to data tampering and denial of service." This is the full extent of the technical detail available from the authoritative source. No specific function names, API endpoints, parameter names, file paths, or code-level implementation details are provided in the CVE data.

From a vulnerability-class perspective, XML injection (CWE-91) occurs when an application fails to properly neutralize special XML characters (such as <, >, &, ', ") within user-supplied input before that input is incorporated into an XML document, XML query (XPath/XQuery), or XML-based configuration structure. Unlike XML External Entity (XXE, CWE-611) injection, which focuses on entity resolution and file disclosure, CWE-91 focuses on the injection of arbitrary XML structures or XPath query manipulation. The consequences can include:

1. Data Tampering (Integrity Impact: High): An attacker can inject XML elements or attributes that alter the structure of configuration data, potentially modifying values, adding unauthorized entries, or corrupting data stores that rely on XML representation.

2. Denial of Service (Availability Impact: High): Malformed XML payloads, injection of oversized or malformed structures, or injection that breaks downstream XML parsers can cause application crashes, service unavailability, or resource exhaustion.

The CVSS vector indicates:

• Attack Vector (AV:N): Network-exploitable, meaning the attacker can trigger the vulnerability remotely over the network.
• Attack Complexity (AC:H): High complexity — the attacker must meet specific conditions or have detailed knowledge of the target's XML handling logic, potentially requiring a narrow window or specific state.
• Privileges Required (PR:H): High privileges — the attacker must be authenticated with administrative or elevated access to the Infrastructure Controller to inject XML input.
• User Interaction (UI:N): No user interaction required.
• Scope (S:U): Unchanged — the vulnerability does not allow the attacker to affect resources beyond the security scope of the vulnerable component.
• Confidentiality (C:N): No impact to confidentiality.
• Integrity (I:H): High impact to data integrity.
• Availability (A:H): High impact to availability.

The attack surface is likely an administrative interface, configuration endpoint, or management API of the NVIDIA Infrastructure Controller that accepts XML-formatted data. However, without specific technical details in the CVE description, the exact entry point cannot be confirmed.

Exploitation Scenarios

No public PoC or exploit code is available for CVE-2026-65124. The following attack chain is inferred at the vulnerability-class level based strictly on the NVD description and CVSS vector, without fabricating specific implementation details.

1) Reconnaissance/Target Identification An attacker identifies a reachable NVIDIA Infrastructure Controller for Linux instance exposed on the network (AV:N). This may be through Shodan queries (e.g., product:"NVIDIA Infrastructure Controller") or internal network scanning. The attacker must possess valid high-privilege credentials (PR:H), suggesting the target is an administrative or management-plane component accessible to authenticated users.

2) Triggering the XML Injection The attacker locates an input point within the Infrastructure Controller that accepts XML-formatted data — potentially a configuration upload, API request body, or management command interface. The exact endpoint or parameter is not specified in the CVE data. The attacker crafts a payload containing XML metacharacters or XML structural elements designed to be interpreted as part of the target's XML document or query rather than as inert data. Because CWE-91 is the assigned weakness, the application fails to properly escape or validate this input before incorporating it into XML processing logic.

3) Payload/Execution Method At the vulnerability-class level, the attacker submits the crafted XML payload through the identified input vector. The payload may:

• Inject additional XML elements or attributes to alter configuration data (data tampering).
• Inject malformed or recursive XML structures designed to cause parser failure or resource exhaustion (denial of service).
• Manipulate XPath or XML query logic if the input is used in query construction.

The high attack complexity (AC:H) implies that successful exploitation may depend on specific application state, parser behavior, or knowledge of the underlying XML schema.

4) Post-Exploitation Impact Successful exploitation results in high integrity impact (data tampering) and high availability impact (denial of service), as reflected in the CVSS vector. The attacker may alter controller configurations, corrupt data stores, or render the Infrastructure Controller unavailable. Confidentiality is not impacted per the CVSS score. No public evidence of in-the-wild exploitation exists at this time, and no threat actor campaign has been associated with this CVE.

Impact Assessment

The business impact of CVE-2026-65124 is concentrated in the integrity and availability domains, with no confidentiality impact. Organizations running NVIDIA Infrastructure Controller for Linux in data center, cloud, or HPC environments are potentially affected.

• Integrity Impact (High): Data tampering could allow an attacker to modify infrastructure configurations, leading to misconfigurations, unauthorized changes, or persistent corruption of management data. This could cascade into broader infrastructure instability.
• Availability Impact (High): Denial of service against the Infrastructure Controller could disrupt management and orchestration operations for dependent systems, potentially causing downtime or degraded service across managed infrastructure.
• Privileges Required (High): The requirement for high privileges significantly narrows the threat actor profile to insiders, compromised administrative accounts, or attackers who have already achieved lateral movement and privilege escalation within the environment.
• Attack Complexity (High): The high complexity reduces the likelihood of opportunistic exploitation and suggests that a successful attack requires detailed knowledge or specific conditions.
• Blast Radius: Because the Infrastructure Controller is a management-plane component, compromise could affect a broad set of downstream managed nodes. However, Scope is Unchanged (S:U), meaning the vulnerability itself does not cross security boundaries.

The CVSS base score of 5.9 (Medium) reflects the balance between high impact and the significant barriers of high complexity and high privilege requirements.

Detection Guidance

Sigma Rule

title: Potential XML Injection Attempt Against NVIDIA Infrastructure Controller
id: 8f4c2b1a-9d3e-4f5a-b6c7-2e1d0a9b8c7d
status: experimental
description: Detects XML injection patterns (CWE-91) in HTTP requests targeting NVIDIA Infrastructure Controller for Linux, based on CVE-2026-65124.
author: Threat Intelligence Team
date: 2026-01-01
logsource:
  category: webserver
  product: linux
detection:
  selection_method:
    cs-method:
      - 'POST'
      - 'PUT'
      - 'PATCH'
  selection_uri:
    cs-uri-stem|contains:
      - '/api/'
      - '/config/'
      - '/admin/'
      - '/controller/'
  selection_xml_payload:
    cs-uri-query|contains:
      - '<?xml'
      - '<!DOCTYPE'
      - '<![CDATA['
      - 'SYSTEM'
      - 'PUBLIC'
      - '&lt;'
      - '&#x'
  condition: selection_method and selection_uri and selection_xml_payload
fields:
  - c-ip
  - cs-method
  - cs-uri-stem
  - cs-uri-query
falsepositives:
  - Legitimate XML API requests containing XML declarations
  - Authorized configuration uploads
level: medium
tags:
  - attack.t1190
  - cwe.91
  - cve.2026.65124

YARA Rule

rule CVE_2026_65124_XML_Injection_NVIDIA_Infra_Controller
{
    meta:
        description = "Detects XML injection payload patterns associated with CVE-2026-65124 in NVIDIA Infrastructure Controller for Linux"
        author = "Threat Intelligence Team"
        date = "2026-01-01"
        reference = "https://nvd.nist.gov/vuln/detail/CVE-2026-65124"
        cve = "CVE-2026-65124"
        cwe = "CWE-91"

    strings:
        $xml_decl = "<?xml version=" ascii nocase
        $doctype = "<!DOCTYPE" ascii nocase
        $entity_sys = "SYSTEM" ascii nocase
        $entity_pub = "PUBLIC" ascii nocase
        $cdata = "<![CDATA[" ascii
        $xpath_expr = "xpath" ascii nocase
        $nvidia_ic = "Infrastructure Controller" ascii nocase
        $nvidia = "NVIDIA" ascii nocase

    condition:
        filesize < 1MB and
        (
            ($xml_decl and $doctype) or
            ($xml_decl and $entity_sys) or
            ($doctype and $entity_pub) or
            ($cdata and ($xpath_expr or $nvidia_ic))
        ) and
        ($nvidia or $nvidia_ic)
}

Suricata IDS Rule

alert http any any -> any any (msg:"CVE-2026-65124 Potential XML Injection Against NVIDIA Infrastructure Controller"; flow:established,to_server; http.method; content:"POST"; http.uri; content:"/api/"; http.request_body; content:"<?xml"; http.request_body; content:"<!DOCTYPE"; http.request_body; content:"SYSTEM"; sid:202665124; rev:1; reference:cve,2026-65124; reference:url,nvd.nist.gov/vuln/detail/CVE-2026-65124; classtype:web-application-attack; metadata:attack_target Server, deployment Perimeter, signature_severity Major;)

Note: A broader rule may also target the PUT and PATCH methods if the vulnerable endpoint accepts them. However, without confirmed endpoint details from the CVE description, this rule uses common administrative API patterns (/api/) and XML injection indicators.

Elastic Detection

sequence by host.name, source.ip with maxspan=30s
  [network where network.protocol == "http" and http.request.method in ("POST", "PUT", "PATCH") and
   url.path : ("/api/*", "/config/*", "/admin/*", "/controller/*")]
  [network where network.protocol == "http" and
   http.request.body.content : ("<?xml*", "*<!DOCTYPE*", "*<![CDATA[*")]
   and http.request.body.content : ("*SYSTEM*" or "*PUBLIC*" or "*&#x*")]

Splunk SPL Query

index=web OR index=proxy OR index=network
(sourcetype=http OR sourcetype=stream:http OR sourcetype=access_combined)
(
  (http_method=POST OR http_method=PUT OR http_method=PATCH)
  AND (uri_path="*/api/*" OR uri_path="*/config/*" OR uri_path="*/admin/*" OR uri_path="*/controller/*")
  AND (form_data="*<?xml*" OR form_data="*<!DOCTYPE*" OR form_data="*<![CDATA[*" OR form_data="*SYSTEM*" OR form_data="*PUBLIC*")
)
| stats count min(_time) as first_seen max(_time) as last_seen
  values(uri_path) as targeted_paths
  values(http_method) as methods
  by src_ip, dest_ip, host
| where count > 0
| sort - count
| convert ctime(first_seen) ctime(last_seen)

Wazuh OSSEC Rule

<group name="web,appsec,nvidia,cve-2026-65124,">
  <rule id="10065124" level="10">
    <if_sid>31100</if_sid>
    <description>CVE-2026-65124: Potential XML injection attempt against NVIDIA Infrastructure Controller</description>
    <match>POST|PUT|PATCH</match>
    <regex type="pcre2">(?i)(/api/|/config/|/admin/|/controller/).*(&lt;\?xml|&lt;!DOCTYPE|&lt;!\[CDATA\[|SYSTEM|PUBLIC)</regex>
    <group>web_attack,xml_injection,cve_2026_65124,</group>
  </rule>

  <rule id="10065125" level="12">
    <if_sid>10065124</if_sid>
    <description>CVE-2026-65124: High-confidence XML injection payload with DOCTYPE/entity declaration targeting NVIDIA Infrastructure Controller</description>
    <regex type="pcre2">(?i)&lt;!DOCTYPE.*(SYSTEM|PUBLIC)</regex>
    <group>web_attack,xml_injection,cve_2026_65124,</group>
  </rule>

  <rule id="10065126" level="8">
    <if_sid>31100</if_sid>
    <description>CVE-2026-65124: XML content submitted to NVIDIA Infrastructure Controller administrative endpoint</description>
    <regex type="pcre2">(?i)(/api/|/config/|/admin/|/controller/).*&lt;\?xml</regex>
    <group>web_attack,xml_injection,cve_2026_65124,</group>
  </rule>
</group>

Mitigation & Patch Guidance

Patch confidence is 0/4 — UNPATCHED. No patch evidence is available from any tracked source, no vendor fix has been published, and no workarounds are documented. The following guidance is based on standard defensive practices for XML injection vulnerabilities (CWE-91) and should be adapted as vendor information becomes available.

1) Immediate Mitigations

• Restrict network access to the NVIDIA Infrastructure Controller management interface. Place it behind a management VLAN, VPN, or jump host and never expose it directly to untrusted networks or the public internet. This directly counters the AV:N vector.
• Enforce least privilege and strong authentication for all accounts with access to the controller. The PR:H requirement means that only high-privileged accounts can exploit this flaw; reducing the number of such accounts and monitoring their activity limits exposure.
• Deploy the detection rules in the Detection Guidance section (Sigma, Suricata, Elastic, Splunk, Wazuh) to identify XML injection attempts in web and API traffic.
• Enable application and web server logging for all requests to the controller, capturing full request bodies where feasible, to support forensic analysis.

2) Patch/Upgrade Steps

• Monitor NVIDIA's official security advisory page and the NVD entry for CVE-2026-65124 for a vendor-issued patch. No patch currently exists.
• When a patch is released, test it in a non-production environment, then apply it to all affected NVIDIA Infrastructure Controller for Linux deployments on an emergency change schedule given the integrity and availability impact.
• Subscribe to NVIDIA security bulletins and CISA advisories to receive timely notification.

3) Long-Term Hardening

• Input validation and output encoding: Ensure that any XML processing within the controller environment uses secure parsers configured to disable external entity resolution and DTD processing where not required. While the vendor controls the application code, validating any integration or custom XML feeds into the controller is a defense-in-depth measure.
• Network segmentation: Maintain strict separation between management-plane components and data-plane or user-facing networks.
• Privileged access management (PAM): Implement session recording, just-in-time access, and MFA for all administrative access to infrastructure controllers.
• Continuous monitoring: Retain and review logs for XML injection indicators and anomalous administrative activity.
• Vulnerability management: Track CVE-2026-65124 and re-assess risk as EPSS scores and vendor patches become available.

References

1. NVD — CVE-2026-65124: https://nvd.nist.gov/vuln/detail/CVE-2026-65124
2. CWE-91: XML Injection — https://cwe.mitre.org/data/definitions/91.html
3. NVIDIA Product Security Advisories — https://www.nvidia.com/en-us/security/
4. CISA Known Exploited Vulnerabilities Catalog — https://www.cisa.gov/known-exploited-vulnerabilities-catalog (CVE-2026-65124 is NOT listed as of this report)
5. FIRST EPSS — https://www.first.org/epss/ (CVE-2026-65124 not yet scored at time of writing)

No threat actor campaigns, exploit-in-the-wild evidence, public PoC, or Nuclei templates have been identified for CVE-2026-65124. The vulnerability is not listed in CISA KEV. All exploitation descriptions in this report are inferred from the vulnerability class (CWE-91) and CVSS vector, not from observed attacks.