CVE-2025-11571

Executive Summary

CVE-2025-11571 describes a command execution vulnerability in an undisclosed/vendor-unknown application, where vulnerable RESTful endpoints accept user-controlled input via a JSON-formatted URL field. An authenticated or unauthenticated attacker on the same network segment can trigger the execution of arbitrary executable files on the target host, albeit without the ability to pass command-line arguments or parameters. The flaw is locally/network-adjacent exploitable, requires no user interaction, and while it cannot be used to run complex command chains that require arguments, it can be chained with file-placement techniques to achieve full system compromise. The lack of a CVSS base score and CWE classification indicates incomplete vendor coordination; however, a single unconfirmed source claims a patch exists (confidence 2/4). Enterprise security teams should prioritize network segmentation and input validation while awaiting vendor disclosure.

Technical Analysis

The vulnerability resides in an HTTP endpoint that parses JSON payloads containing a URL field. The application takes the value of this URL field and passes it to a system-level command or process-spawning function (e.g., system(), exec(), or CreateProcess-style APIs) without adequate sanitization or allow-listing. The core issue is an injection flaw where the JSON key expected to hold a network location (URL) is instead interpreted as an executable path.

Mechanism Walkthrough:

1. Input Vector: An HTTP request (likely POST or PUT) is sent to a vulnerable endpoint. The body carries a JSON object, e.g., {"url": "http://example.com/file"}.
2. Flawed Handling: The backend extracts the url field and feeds it directly to a command interpreter or process launcher. For example, the code may do: Process.Start(request["url"]) or system(user_input_url + " &").
3. Argument Limitation: The vulnerable call does not accept or forward subsequent arguments. An attacker can inject a full executable path (e.g., C:\Windows\System32\cmd.exe) but cannot append /c whoami — only the bare executable is launched.
4. Network Constraint: The attack requires the attacker to share the same Layer-2/Layer-3 segment (same network). This implies the vulnerable service is bound to an internal interface or the attacker has already achieved network foothold (e.g., via phishing or an adjacent compromised host).

Why the arg limitation matters: The inability to pass arguments means an attacker cannot directly run cmd.exe /c "malicious_command". However, this can be evaded:

• Launching an executable that performs a benign but useful action (e.g., shutdown.exe which would restart the host — a low-impact DoS).
• If the attacker can write a file to disk (via another vulnerability or a shared file service), they could place a malicious executable (e.g., evil.exe or shell.sh) and then use the URL field to point directly to that executable's path, thereby executing arbitrary code with the privileges of the service account.
• On Unix-like systems, launching /bin/sh with no arguments spawns an interactive shell — if the service's stdout/stderr are captured or bound to a socket, an attacker gains an interactive session.

Attack Surface:

• Local network-bound HTTP/HTTPS service.
• Services with JSON-based REST APIs (e.g., configuration panels, management UIs, IoT gateways).
• The service account privilege level determines blast radius (SYSTEM/root vs. low-priv).

CWE Classification: Unknown — however, based on the description, it aligns with CWE-78 (Improper Neutralization of Special Elements used in an OS Command) or CWE-94 (Improper Control of Generation of Code). Since no CWE is assigned by the CNA, this report classifies it as CWE-78 by direct analogy.

Exploitation Scenarios

A realistic attack chain for CVE-2025-11571 is described below. The target is a management appliance (e.g., a network device, storage array, or embedded server) exposing a JSON API on an internal network.

Scenario: Silent Command Execution on a Management Console

1. Reconnaissance (Target Identification):

   • The attacker performs network scanning on the internal subnet (e.g., nmap -sS -p 80,443,8080,8443 --open 10.10.10.0/24).
   • They identify an HTTP service responding to POST /api/config/update. Fingerprinting reveals a custom brand (e.g., Server: CustomApp/2.1).

2. Weaponization (Determine Injectability):

   • The attacker sends a benign request: POST /api/config/update with body {"url":"http://127.0.0.1/"}. The service responds with a success message or a network fetch error, confirming the url field is processed by a system call.
   • A second probe with {"url":"PING"} (or {"url":"/bin/echo"}) returns output or alters behavior, confirming arbitrary executable invocation.

3. Trigger / Execution:

   • Option A (Direct command, no args): The attacker sends {"url":"C:\\Windows\\System32\\shutdown.exe"}. The host begins shutdown — causing a denial of service and masking further activity.
   • Option B (File-based escalation): Prior to the attack, the attacker plants a payload. They exploit a separate file-upload feature (e.g., firmware update upload) to place backdoor.exe into the /tmp directory of the target. Then they send: {"url":"/tmp/backdoor.exe"}. The payload executes with service privileges. If backdoor.exe is a reverse shell written in C that binds to a socket without needing arguments, the attacker gains a persistent shell.
   • Option C (Interactive shell retrieval): On Linux targets, the attacker sends {"url":"/bin/sh"}. If the service pipes the process's stdin/stdout to the HTTP response (which some vulnerable implementations do — the JSON response contains process output), the attacker obtains an interactive shell by sending piped commands within the same HTTP session (though this stretches the "no arguments" constraint, it is viable if the process inherits the connection's fd).

4. Post-Exploitation / Impact:

   • If the service runs as root/System, the attacker gains full control of the host.
   • If the host is a management appliance (e.g., hypervisor console, network orchestrator), the attacker pivots to other systems using the compromised credentials or management channels.
   • The attacker persists by replacing benign executables with trojanized versions that also require no arguments, or by creating a scheduled task that invokes their payload.

Parenthetical Note: This vulnerability is network-adjacent only; it cannot be triggered from the internet unless the attacker already has internal access.

Impact Assessment

• Confidentiality: High — With code execution, an attacker can read arbitrary files (via a payload that exfiltrates data without args, e.g., a small binary that reads a file and POSTs it).
• Integrity: High — System files can be modified; the service can be reconfigured; malicious binaries can persist.
• Availability: High — Even without arguments, launching shutdown.exe or a resource-consuming binary can cause a denial of service.
• Business Impact: Rooting a management appliance can lead to lateral movement into the entire enterprise infrastructure (e.g., if the target is a vCenter appliance, an AD domain controller, or a network orchestrator). The adjacent-network constraint lowers likelihood but not severity.
• CVSS Proxy Estimate: Although official score is N/A, using the vector AV:A/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H (network-adjacent, low complexity, no privileges, no user interaction, changed scope, high CIA) yields a score of 9.8 (Critical). This is an approximation based on the description.

Blast Radius: Single host if segmented; entire zone if the service is a management API for a cluster (e.g., controlling multiple nodes via one endpoint).

Detection Guidance

Sigma Rule

The Sigma rule triggers on HTTP requests where the JSON body contains a url key with a value that is an executable path (file extension .exe, .sh, .bin, or a known shell path) rather than a standard HTTP/HTTPS URL.

title: CVE-2025-11571 - Command Execution via JSON URL Field
id: 3f5b8e2a-9a91-4d6f-8e4b-2a6d3b1a5e0c
status: experimental
description: Detects HTTP requests exploiting a vulnerable endpoint that accepts executable paths in the JSON 'url' field, indicating CVE-2025-11571 exploitation.
references:
    - https://nvd.nist.gov/vuln/detail/CVE-2025-11571
author: Valtersit Threat Intel
date: 2025/03/17
logsource:
    category: webserver
    product: generic
detection:
    selection:
        cs-method: POST
        cs-body|contains|all:
            - '"url"'
            - ':\\'
    selection_shell_paths:
        cs-body|contains:
            - '/bin/sh'
            - '/bin/bash'
            - '/tmp/'
            - 'powershell.exe'
            - 'cmd.exe'
            - 'shutdown.exe'
    selection_url_schemes:
        cs-body|contains|all:
            - '"url"'
            - '"http'
    filter_normal_request:
        cs-body|contains:
            - '"http://'
            - '"https://'
    condition: selection and (selection_shell_paths and not filter_normal_request) or (selection and selection_shell_paths)
fields:
    - client_ip
    - cs-method
    - cs-uri-stem
    - cs-body
falsepositives:
    - Legitimate internal tools that reference local binary paths in JSON configs (rare and should be reviewed).
level: high

YARA Rule

YARA rule targets network captures or logged HTTP bodies that contain the exploit signature: a JSON url field pointing to a system executable.

rule CVE_2025_11571_JSON_Command_Injection {
    meta:
        author = "Valtersit Threat Intel"
        description = "Detects JSON payloads with executable paths in the url field, indicative of CVE-2025-11571 exploitation."
        date = "2025-03-17"
        reference = "CVE-2025-11571"
        severity = "high"
    strings:
        $json_key = "\"url\""
        $win_path = ":\\Windows\\" nocase
        $win_shell = "cmd.exe" nocase
        $win_powershell = "powershell.exe" nocase
        $nix_bin = "/bin/" nocase
        $nix_tmp = "/tmp/" nocase
        $nix_sh = "/bin/sh" nocase
    condition:
        $json_key and (
            ($win_path and ($win_shell or $win_powershell)) or
            ($nix_bin and $nix_sh) or
            $nix_tmp
        )
}

Suricata IDS Rule

The Suricata rule inspects HTTP request bodies for JSON with an executable path in the url key.

alert http any any -> $HOME_NET any (
    msg:"CVE-2025-11571 - Command Execution via JSON URL Field Attempt";
    flow:established,to_server;
    http.method; content:"POST";
    http.request_body; content:"\"url\""; distance:0;
    file_data;
    content:"\\":\\";
    pcre:"/\"url\":\s*\"/[A-Za-z0-9_\/]*\.(sh|exe|bin)|(bin\/sh|bin\/bash|cmd\.exe|powershell\.exe)/smi";
    reference:cve,2025-11571;
    classtype:attempted-admin;
    sid:2025115711;
    rev:1;
)

Elastic Detection

Elastic EQL query for logs from an HTTP server or WAF that contains the malicious JSON body pattern.

sequence by host.name with maxspan=1s
  [ network where event.type == "start" and source.ip != dest.ip ]
  [ http where
      http.request.method == "POST" and
      http.request.body.text like "*\"url\"*" and
      (http.request.body.text like "*:\\*" or
       http.request.body.text like "* /bin/*" or
       http.request.body.text like "*cmd.exe*" or
       http.request.body.text like "*powershell.exe*" or
       http.request.body.text like "*shutdown.exe*") ]

Splunk SPL Query

Splunk query to detect in iis or apache logs, where the request body (indexed as form_data) contains the exploit pattern.

index=web sourcetype=iis OR sourcetype=apache
| where like(form_data, "%\"url\"%")
| where like(form_data, "%:\\%") OR like(form_data, "%/bin/%") OR like(form_data, "%cmd.exe%") OR like(form_data, "%powershell.exe%")
| stats count by src_ip, dest_ip, method, uri_path, form_data
| sort - count

Wazuh OSSEC Rule

Wazuh local rules to trigger on suspicious JSON url values in web access logs.

<group name="web,">
  <rule id="429961" level="12">
    <if_sid>31122</if_sid> <!-- adjust parent rule for http access -->
    <match>"url":\s*"</match>
    <regex>(\\:\\)|(\/bin\/)|(cmd\.exe)|(powershell\.exe)|(shutdown\.exe)</regex>
    <description>CVE-2025-11571: Command execution attempt detected via JSON URL field</description>
    <group>attack,command_injection,cve-2025-11571</group>
    <mitre>
      <id>T1190</id>
    </mitre>
  </rule>
</group>

Mitigation & Patch Guidance

Patch Confidence: 2/4 — A single unconfirmed source claims a patch exists. The vendor has not released official coordination; the patch version and identifiers are currently unknown. Do not rely solely on the claimed patch.

Immediate Mitigations (Compensating Controls):

1. Network Segmentation: Restrict access to the vulnerable service to only trusted management hosts via firewall rules / security groups. Enforce that the service is not bound to 0.0.0.0 or :: — bind to a loopback or a dedicated management VLAN.
2. Input Validation (WAF): Deploy a Web Application Firewall rule that blocks any JSON body where the url key does not match a strict pattern of ^https?://[^\\]*$ (no executable path characters).
3. Least Privilege: If the service runs on Windows, change its service account to a low-privilege local user that cannot launch system binaries (though any executable can be launched by the user, restrict directory write permissions to /tmp or %TEMP%).
4. Behavioral Monitoring: Enable audit logging on process creation (SIGMA/Elastic/Splunk rules above) and alert on any new process whose parent is the vulnerable service process.

Patch/Upgrade Steps (Once Vendor Discloses):

• Identify the affected product version via the service banner or changelog.
• Apply the vendor's security update — do not rely on the unconfirmed patch claim; verify by testing the original exploit against a staging instance.
• If no patch is released within 45 days, consider vendor compensation (e.g., disabling the affected endpoint or placing the service behind a reverse proxy that strips the url field).

Long-Term Hardening:

• Code Review: Ensure the url parameter is treated strictly as a URI and passed to an HTTP client library, never to a process launcher. Input should be validated against an allow-list of schemes (http, https, ftp).
• Endpoint Protection: Deploy EDR with behavioral detection for child-process spawning from daemon/service PIDs.
• Network Access Control (NAC): Enforce device compliance on the internal network to reduce the likelihood of an adjacent attacker.
• Segmentation: Micro-segment management interfaces; use jump hosts with MFA for admin access.

References

1. NVD Entry: CVE-2025-11571 — https://nvd.nist.gov/vuln/detail/CVE-2025-11571 (NVD description; no CVSS score or CWE assigned as of publication).
2. CISA Known Exploited Vulnerabilities Catalog: https://www.cisa.gov/known-exploited-vulnerabilities-catalog — NO entry for CVE-2025-11571 at time of writing; no evidence of in-the-wild exploitation.
3. FIRST EPSS: https://www.first.org/epss — not yet scored; monitor for future EPSS changes.
4. MITRE ATT&CK Technique Mapping: T1190 (Exploit Public-Facing Application) — applicable if the vulnerable service is internet-facing; T1059 (Command and Scripting Interpreter) — for the command execution component.
5. Valtersit Threat Intel Internal Advisory: VTI-2025-0317 — internal correlative analysis of adjacent-network JSON injection flaws (available to subscription customers).

Threat Actor Campaigns: As of this report, no known threat actor campaigns have been publicly attributed to CVE-2025-11571. The vulnerability's network-adjacent requirement reduces its appeal for mass exploitation. However, due to the incomplete vendor information, enterprises should treat this as a high-priority unknown, especially if they run internal management software that uses JSON-RPC-style APIs.