CVE-2026-0587

Executive Summary

CVE-2026-0587 describes a Cross-Site Scripting (XSS) vulnerability affecting Xinhu Rainrock RockOA, specifically in versions up to 2.7.1. The flaw resides within the rock_page_gong.php file, part of the "Cover Image Handler" component, where manipulation of the fengmian argument allows for remote script injection. A public exploit for this vulnerability exists, increasing the urgency for mitigation, especially given the vendor's unresponsiveness and the absence of an official patch.

Technical Analysis

This vulnerability, identified as CWE-79 (Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')), manifests in the rock_page_gong.php file within the Xinhu Rainrock RockOA application. The core mechanism involves insufficient sanitization or encoding of user-supplied input when processing the fengmian argument, which is associated with the "Cover Image Handler" component.

An attacker can craft a malicious request where the fengmian argument contains arbitrary client-side script code (e.g., JavaScript). When a legitimate user's browser renders a page that incorporates the manipulated fengmian value (likely in the context of displaying a cover image or related content handled by rock_page_gong.php), the injected script is executed within the user's browser session.

The vulnerability is remote, meaning an attacker does not need direct access to the server or specific network segmentation to initiate the attack. The lack of proper input validation or output encoding on the server-side allows the malicious payload to be stored or reflected and subsequently rendered by client browsers. While specific implementation details of the rock_page_gong.php file are not publicly detailed, the core issue is a failure to escape or sanitize user-controlled data before it is embedded into the HTML context of a web page. This results in the client's browser interpreting the injected data as executable code rather than harmless content. The NVD description indicates that the vulnerability affects an "unknown function" within this file, suggesting the flaw is within the processing logic of the fengmian parameter.

Exploitation Scenarios

Exploitation of CVE-2026-0587 involves a multi-stage attack targeting the client-side execution environment of Xinhu Rainrock RockOA users. The attack chain, inferred from the Cross-Site Scripting (XSS) vulnerability class and remote accessibility, proceeds as follows:

1. Reconnaissance/Target Identification: An attacker first identifies publicly accessible instances of Xinhu Rainrock RockOA. This can be achieved using search engines or specialized services like Shodan, leveraging dorks such as http.title:RockOA or http.html:"Xinhu Rainrock RockOA". The attacker aims to find an instance where the rock_page_gong.php endpoint is accessible and processes the fengmian argument.

2. Triggering the Flaw: The attacker crafts a malicious HTTP request (typically GET or POST, depending on the application's implementation for handling fengmian) to the rock_page_gong.php endpoint. Within this request, the fengmian argument is manipulated to include an XSS payload. For example, a request might look like: GET /rock_page_gong.php?fengmian=<script>alert('XSS');</script> or GET /rock_page_gong.php?fengmian=<img src=x onerror=alert(document.cookie)> The application, lacking proper input validation and output encoding, stores or reflects this malicious input.

3. Payload Execution: The malicious payload is not immediately executed on the attacker's machine. Instead, it is stored or reflected within the application's content (e.g., a "Cover Image" display page). When another legitimate user (the victim) browses to a part of the Xinhu Rainrock RockOA application that renders or displays the content associated with the manipulated fengmian argument in rock_page_gong.php, the injected script executes within the victim's web browser in the context of the vulnerable application's domain.

4. Post-Exploitation Impact: Upon successful execution of the injected script, various client-side attacks can be launched:

   • Session Hijacking: The attacker's script can steal session cookies, allowing them to impersonate the victim and gain unauthorized access to their account within the RockOA application.
   • Defacement: The attacker can modify the appearance of the web page seen by the victim, leading to brand damage or misinformation.
   • Client-side Redirection: The victim's browser can be silently redirected to a malicious phishing site or another attacker-controlled domain.
   • Arbitrary Client-Side Code Execution: The attacker can execute any JavaScript code, enabling actions like keylogging, credential harvesting from forms, or initiating requests to other parts of the application (e.g., changing user settings) without the victim's explicit consent.

This attack relies on user interaction (the victim viewing the compromised content) but is considered highly dangerous due to the potential for complete compromise of the victim's session and sensitive data within the application. The fact that a public exploit exists significantly lowers the bar for threat actors to leverage this vulnerability.

Impact Assessment

The XSS vulnerability in Xinhu Rainrock RockOA (CVE-2026-0587) carries a significant impact, primarily affecting the confidentiality and integrity of user data and the overall trust in the application. With a CVSS score of 5.1, it falls into the medium severity category.

• Confidentiality Impact (C:L - Low): While the XSS attack directly affects the client-side, it enables the theft of sensitive information such as session tokens, cookies, and potentially credentials if a malicious script targets input fields. This can lead to unauthorized access to the victim's account within the RockOA application, resulting in a loss of confidentiality for their data. The direct impact is on the user's browser, but the secondary impact extends to the application's data accessed by the user.

• Integrity Impact (I:L - Low): An attacker can modify the content displayed on the victim's web page, leading to defacement or misleading information. More critically, an XSS payload can force the victim's browser to execute actions on behalf of the victim (e.g., posting content, changing settings, deleting data) within the application's context. While the direct integrity of the server-side data might not be compromised, the integrity of the user's interaction and data within their session is.

• Availability Impact (A:N - None): This type of XSS vulnerability typically does not directly lead to a denial of service for the application or its users. The primary goal of an XSS attack is data theft or manipulation, not service disruption.

The blast radius of this vulnerability is broad, impacting any user who interacts with a compromised instance of the Xinhu Rainrock RockOA application. Since the exploit is public and the attack can be launched remotely, the risk of widespread exploitation is elevated. Enterprise security teams need to recognize that even a medium-severity client-side vulnerability, especially with public exploit code, can serve as a stepping stone for more sophisticated attacks or lead to significant reputational damage and data breaches.

Detection Guidance

Sigma Rule

title: Xinhu Rainrock RockOA XSS Attempt (CVE-2026-0587)
id: 00000000-0000-0000-0000-000000000587 # Placeholder UUID
status: experimental
description: Detects potential Cross-Site Scripting (XSS) attempts against Xinhu Rainrock RockOA's rock_page_gong.php via the fengmian parameter.
author: ValterSit SOC Team
date: 2026/01/01
logsource:
  category: webserver
  service: access_log
detection:
  keywords:
    - 'GET /rock_page_gong.php?'
    - 'POST /rock_page_gong.php?'
  selection_fengmian:
    cs-uri-query|contains:
      - 'fengmian='
      - 'fengmian=%3c' # Encoded <
      - 'fengmian=<script'
      - 'fengmian=javascript:'
      - 'fengmian=data:text/html;'
      - 'fengmian=&#x' # HTML entity encoding
      - 'fengmian=%22%3e%3c' # "><
      - 'fengmian=onmouse' # Event handlers
      - 'fengmian=alert('
  condition: keywords and selection_fengmian
level: high
tags:
  - attack.injection
  - attack.t1190
  - cve.2026.0587
  - xss

YARA Rule

rule CVE_2026_0587_Xinhu_RockOA_XSS {
  meta:
    author = "ValterSit SOC Team"
    date = "2026-01-01"
    description = "Detects XSS payloads targeting Xinhu Rainrock RockOA's rock_page_gong.php via the fengmian parameter in HTTP traffic or logs."
    cve = "CVE-2026-0587"
    severity = "HIGH"
    reference = "https://nvd.nist.gov/vuln/detail/CVE-2026-0587"
  strings:
    $endpoint = "rock_page_gong.php" nocase
    $param_fengmian = "fengmian=" nocase
    
    // Common XSS payloads or patterns
    $xss_script1 = "<script>" nocase
    $xss_script2 = "%3cscript%3e" nocase // URL-encoded <script>
    $xss_img = "<img src=" nocase ascii wide
    $xss_onerror = "onerror=" nocase
    $xss_alert = "alert(" nocase
    $xss_javascript = "javascript:" nocase
    $xss_html_entity = "&#x" nocase
    $xss_encoded_quotes_gt = "%22%3e%3c" // "><
    $xss_svg_onload = "<svg onload=" nocase

  condition:
    $endpoint in (0..1000) and $param_fengmian in (0..1000) and 
    (
      $xss_script1 or $xss_script2 or $xss_img or $xss_onerror or 
      $xss_alert or $xss_javascript or $xss_html_entity or 
      $xss_encoded_quotes_gt or $xss_svg_onload
    )
}

Suricata IDS Rule

alert http any any -> any any (msg:"ET WEB_ATTACK Xinhu Rainrock RockOA XSS via rock_page_gong.php (CVE-2026-0587)"; flow:to_server,established; http.uri; content:"rock_page_gong.php"; http.uri; content:"fengmian="; fast_pattern; pcre:"/fengmian=.*(<script|javascript:|&#x|%3cscript%3e|%22%3e%3c)/iU"; classtype:web-application-attack; sid:20260587; rev:1;)

Elastic Detection

{
  "query": {
    "bool": {
      "must": [
        {
          "match_phrase": {
            "url.path": "rock_page_gong.php"
          }
        },
        {
          "match_phrase": {
            "url.query": "fengmian="
          }
        },
        {
          "bool": {
            "should": [
              { "match_phrase": { "url.query": "<script>" } },
              { "match_phrase": { "url.query": "%3cscript%3e" } },
              { "match_phrase": { "url.query": "javascript:" } },
              { "match_phrase": { "url.query": "&#x" } },
              { "match_phrase": { "url.query": "%22%3e%3c" } },
              { "match_phrase": { "url.query": "onerror=" } },
              { "match_phrase": { "url.query": "alert(" } },
              { "match_phrase": { "url.query": "data:text/html" } }
            ]
          }
        }
      ]
    }
  },
  "risk_score": 75,
  "name": "Xinhu Rainrock RockOA XSS Attempt (CVE-2026-0587)",
  "description": "Detects potential Cross-Site Scripting (XSS) attempts against Xinhu Rainrock RockOA's rock_page_gong.php via the fengmian parameter.",
  "severity": "high",
  "tags": ["web_attack", "xss", "cve_2026_0587"]
}

Splunk SPL Query

index=web sourcetype=access_combined (uri_path="/rock_page_gong.php" OR uri_query="rock_page_gong.php*") 
(uri_query="*fengmian=*" AND 
 (uri_query="*<script>*" OR uri_query="*%3cscript%3e*" OR uri_query="*javascript:*" OR 
  uri_query="*&#x*" OR uri_query="*%22%3e%3c*" OR uri_query="*onerror=*" OR 
  uri_query="*alert(*" OR uri_query="*data:text/html*"))
)
| table _time, clientip, uri_path, uri_query, user_agent

Wazuh OSSEC Rule

<group name="web_attacks,xss,cve_2026_0587,">
  <rule id="100001" level="10">
    <if_sid>31100</if_sid> <!-- Apache access log -->
    <field name="url" type="pcre">rock_page_gong.php</field>
    <options>pcre_matchall</options>
    <description>Xinhu Rainrock RockOA XSS attempt (CVE-2026-0587)</description>
    <group>attack,</group>
  </rule>

  <rule id="100002" level="12" overwrite="yes">
    <if_sid>100001</if_sid>
    <options>no_full_log</options>
    <field name="url" type="pcre" nocase="true">fengmian=.*(<script|javascript:|&#x|%3cscript%3e|%22%3e%3c|onerror=|alert\(|data:text/html)</field>
    <description>Xinhu Rainrock RockOA XSS via fengmian parameter in rock_page_gong.php (CVE-2026-0587)</description>
    <mitre>
      <id>T1190</id>
    </mitre>
    <group>attack,web_attack,xss,pci_dss_6.5.1,gdpr_audit_4.1_4.5,gpg13_4.12,hipaa_164.306.a,nist_800_53_AC.4,nist_800_53_AU.12,nist_800_53_SI.4,</group>
  </rule>
</group>

Mitigation & Patch Guidance

Given that CVE-2026-0587 is UNPATCHED and the vendor has not responded to disclosure efforts, immediate and proactive mitigation strategies are critical to protect against potential exploitation.

1. Immediate Mitigations (Temporary Measures):

   • Web Application Firewall (WAF): Implement or configure a WAF to actively block requests to rock_page_gong.php that contain common XSS payloads in the fengmian parameter. WAF rules should focus on detecting script tags (<script>), encoded script tags (%3cscript%3e), JavaScript URIs (javascript:), HTML entities (&#x), and other XSS-related keywords or patterns.
   • Input Validation at Network Edge: If possible, implement server-side input validation or pre-processing rules on proxy servers or load balancers to filter out malicious input before it reaches the vulnerable application. This should strictly sanitize or reject input for the fengmian argument that contains HTML or script-like characters.
   • Content Security Policy (CSP): Implement a stringent Content Security Policy (CSP) header on web servers hosting Xinhu Rainrock RockOA. A well-configured CSP can significantly reduce the impact of XSS attacks by restricting the sources from which scripts, styles, and other resources can be loaded, and by disallowing inline scripts.
   • Browser-Side Protections: Advise end-users to employ browser extensions that block client-side scripting (e.g., NoScript) on untrusted sites or to be cautious of unusual pop-ups or behaviors when interacting with the application.

2. Patch/Upgrade Steps (Long-Term Solution):

   • Monitor Vendor for Official Patch: Continuously monitor Xinhu's official channels and security advisories for the release of an official patch or updated version of Rainrock RockOA that addresses CVE-2026-0587. As soon as a patch is available, prioritize its deployment.
   • Vendor Contact: Continue attempts to contact the vendor (Xinhu) to encourage the development and release of a security patch. Collaborate with other affected organizations if possible to amplify the request.

3. Long-Term Hardening (Proactive Security):

   • Secure Coding Practices: If custom development or modifications are made to the RockOA platform, ensure all user-supplied input is properly validated, sanitized, and output-encoded (e.g., HTML entity encoding, URL encoding) before being rendered back to the user's browser. This adheres to the principle of "never trust user input."
   • Regular Security Audits: Conduct periodic security assessments, penetration tests, and code reviews of the Xinhu Rainrock RockOA installation to identify and remediate similar vulnerabilities.
   • Least Privilege Principle: Ensure that the web server process running RockOA operates with the minimum necessary privileges to reduce the impact of a full server compromise if other vulnerabilities are exploited.
   • Security Awareness Training: Train users and administrators on recognizing phishing attempts and malicious links, as XSS attacks often rely on social engineering to lure victims into interacting with compromised content.

References

1. National Vulnerability Database (NVD) - CVE-2026-0587: https://nvd.nist.gov/vuln/detail/CVE-2026-0587
2. CNA Advisory (Implicit): While no direct link to a Xinhu advisory exists due to vendor unresponsiveness, the vulnerability details originate from the CNA title: "Xinhu Rainrock RockOA Cover Image rock_page_gong.php cross site scripting". Specific vendor advisory pending release.
3. OWASP Cross-Site Scripting (XSS) Prevention Cheat Sheet: https://cheatsheetseries.owasp.org/cheatsheets/Cross_Site_Scripting_Prevention_Cheat_Sheet.html
4. Public Exploit Details: Information regarding the public exploit for CVE-2026-0587 should be actively monitored on platforms like Exploit-DB, GitHub, or specialized security research blogs as they emerge. No specific link is provided in the initial disclosure.
5. CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting'): https://cwe.mitre.org/data/definitions/79.html