CVE-2026-77036

Executive Summary

CVE-2026-77036 is an improper authorization vulnerability (CWE-266) affecting elunez eladmin up to version 2.7, a widely used Java-based administration and rapid-development platform. The flaw resides in the email, AliPay payment, code generator, and generator configuration modules, allowing an authenticated low-privilege attacker to perform unauthorized operations remotely. With a CVSS base score of 6.3 and an exploit publicly disclosed, this vulnerability poses a moderate but immediate risk to production deployments, potentially leading to unauthorized data access, configuration tampering, and disruption of code-generation workflows.

Technical Analysis

Vulnerability Class & Mechanism:
The vulnerability is classified under CWE-266 (Incorrect Privilege Assignment). The NVD description identifies four impacted components: EmailController, AliPayController, GeneratorController, and GenConfigController. The core issue is that these endpoints fail to enforce proper authorization checks, allowing any authenticated user — regardless of their assigned role or privilege level — to invoke administrative functions. This is a classic broken access control scenario where the application relies on implicit trust in the authenticated session rather than explicit role-based authorization for each sensitive operation.

Attack Surface:
Eladmin is a Spring Boot-based administrative framework. The affected controllers expose RESTful API endpoints designed for administrative tasks:

• EmailController: Handles email server configuration and test email sending — typically admin-only functionality.
• AliPayController: Manages Alipay payment gateway credentials and transaction operations.
• GeneratorController: Provides code generation capabilities for rapid scaffolding of CRUD modules — dangerous if abused for source code exfiltration.
• GenConfigController: Manages generator configuration templates and database connection settings for the generator.

The attack surface is network-facing (AV:N in CVSS vector) and requires only low-privilege authentication (PR:L). No user interaction is needed (UI:N), and the attack does not require special conditions beyond network access to the application.

Technical Detail Gaps:
The NVD description does not specify the exact authorization bypass mechanism — whether it is a missing @PreAuthorize annotation in Spring Security, flawed method-level security configuration, or improper role checks in service-layer methods. Insufficient technical detail is available to pinpoint the precise code-level flaw; however, the vulnerability class (incorrect privilege assignment) strongly suggests the endpoints lack the required role-based access control (RBAC) annotations or checks that should restrict them to admin roles.

Scope & Impact Vector:
The CVSS vector indicates limited impact per subscore (C:L/I:L/A:L) — confidentiality, integrity, and availability are all partially impacted. However, the code generator modules could amplify real-world impact: unauthorized access to GeneratorController could allow extraction of application source code, database schemas, and internal business logic, significantly increasing the effective data loss beyond what the CVSS subscore suggests.

Exploitation Scenarios

Step 1: Reconnaissance & Target Identification
An attacker with valid low-privilege credentials (e.g., a regular user account, possibly obtained through credential stuffing or prior compromise) first identifies the eladmin deployment. Shodan or Fofa queries for "eladmin" title or body content can locate exposed instances. The default admin panel path is typically /login or /admin; after authentication, the attacker enumerates accessible API routes to identify which of the four affected controllers are reachable from their session.

Step 2: Triggering the Authorization Flaw
The attacker directly invokes the affected endpoints without attempting privilege escalation. For example, a standard GET request to the code generator configuration endpoint (GenConfigController) that should be restricted to administrators is processed successfully because the authorization check is absent or insufficient. No crafted payload is needed for the bypass itself — the flaw is in missing access control, not input validation.

Step 3: Payload/Execution Method (Vulnerability-Class Level)
Since the vulnerability is improper authorization rather than injection, the "payload" is simply the legitimate API request syntax that only admin should be able to make. Attack patterns include:

• Retrieving email server credentials (SMTP passwords) from the EmailController.
• Modifying Alipay merchant configuration to redirect payments or alter transaction settings.
• Triggering code generation for modules that expose sensitive internal logic or overwriting existing source files.
• Reading or modifying generator configuration to alter code templates, potentially injecting malicious code into subsequently generated modules.

Step 4: Post-Exploitation Impact
Successful exploitation grants the attacker administrative-level operations without admin privileges. This enables:

• Credential Harvesting: Email/DB credentials exposed via configuration endpoints.
• Integrity Compromise: Altering payment configurations or generator templates to inject malicious code into future project scaffolding.
• Lateral Movement: Using extracted credentials to access other systems (database, SMTP server, payment gateway).
• Availability: Disrupting code generation workflows or modifying critical configuration files.

PoC Notice: The NVD description states the exploit has been made public, though no specific PoC code or technical write-up details are available in this intelligence data. The attack chain above is inferred from the vulnerability class and the identified components.

Impact Assessment

Business Impact:
Eladmin is commonly used as an internal administration platform for Java projects. Successful exploitation grants low-privilege users unauthorized access to sensitive system configurations. The business impact is threefold:

1. Confidentiality: Exposure of email server credentials, Alipay merchant keys, and database connection strings.
2. Integrity: Modification of payment configurations could redirect transaction callbacks or alter merchant settings, potentially leading to financial fraud.
3. Availability: Disruption of the code generation pipeline can halt development operations.

Affected Systems:
All deployments of elunez eladmin version 2.7 and earlier. Given the platform's popularity in Chinese enterprise environments and its use in many open-source projects (the GitHub repository has thousands of stars), the potential blast radius includes numerous production systems.

CVSS Subscore Relevance:
The CVSS:3.1 score of 6.3 (Medium) with C:L/I:L/A:L reflects the limited per-impact scores. However, real-world exploitation tying together these limited impacts — e.g., extracting SMTP credentials and then using them to send phishing emails from the corporate domain — can create consequences exceeding the CVSS rating. The low attack complexity and low privilege requirement make this an attractive target for automated exploitation.

Detection Guidance

Sigma Rule

title: Eladmin Improper Authorization - Low Privilege Access to Admin Controllers
id: 3f7d9c2a-5b8e-4a1c-9d3f-6a2b8c9d1e4f
status: experimental
description: Detects low-privilege user accounts accessing admin-restricted eladmin controllers (Email, AliPay, Generator, GenConfig)
author: Valtersit Threat Intelligence
date: 2026/07/01
logsource:
  category: application
  product: eladmin
  service: web
detection:
  selection:
    http.response.body|contains:
      - 'email'
      - 'aliPay'
      - 'generator'
      - 'genConfig'
    http.response.status_code: 200
  filter_known_admin:
    user.roles|contains: 'admin'
  condition: selection and not filter_known_admin
level: high
falsepositives:
  - Legitimate admin delegation where a system account with non-admin role is used for automation
tags:
  - attack.t1190
  - cve.2026.77036
  - cwe.266

YARA Rule

rule eladmin_improper_auth_logs
{
    meta:
        author = "Valtersit Threat Intelligence"
        description = "Detect access to admin controllers in eladmin logs that may indicate CVE-2026-77036 exploitation"
        cve = "CVE-2026-77036"
        date = "2026-07-01"
        severity = "high"
    strings:
        $s1 = "EmailController" ascii nocase
        $s2 = "AliPayController" ascii nocase
        $s3 = "GeneratorController" ascii nocase
        $s4 = "GenConfigController" ascii nocase
        $s5 = "GET" ascii
        $s6 = "POST" ascii
        $s7 = "PUT" ascii
    condition:
        any of ($s1*) and any of ($s5*) 
        and filesize < 5MB
}

Suricata IDS Rule

alert http any any -> $HOME_NET any (msg:"ELADMIN CVE-2026-77036 - Unauthorized Access to Admin Controller Endpoint"; \
flow:established,to_server; \
http.method; content:"GET"; http.uri; content:"/api/"; \
content:"email"; nocase; \
http.uri; content:"/api/"; \
content:"generator"; nocase; \
http.uri; content:"/api/"; \
content:"aliPay"; nocase; \
http.uri; content:"/api/"; \
content:"genConfig"; nocase; \
sid:202677036; rev:1; \
reference:cve,2026-77036; \
metadata:attack_target Web_Server, deployment Perimeter, tag CVE-2026-77036, signature_severity Major)

Elastic Detection

sequence by source.ip with maxspan=5m
  [any where process.name == "java" and 
   event.action in ("request", "execute") and
   http.request.body.content contains "EmailController" or 
   http.request.body.content contains "AliPayController" or 
   http.request.body.content contains "GeneratorController" or 
   http.request.body.content contains "GenConfigController"]
  [any where user.roles != "admin" and 
   event.action == "success" and
   http.request.method in ("GET", "POST", "PUT")]

Splunk SPL Query

index=web sourcetype=access_combined
| where like(uri, "%EmailController%") OR like(uri, "%AliPayController%") 
   OR like(uri, "%GeneratorController%") OR like(uri, "%GenConfigController%")
| where NOT match(user_roles, "admin")
| stats count by username, src_ip, uri, _time
| sort - _time
| table _time, username, src_ip, uri, count
| eval suspicious = if(count > 5, "REVIEW", "monitor")

Wazuh OSSEC Rule

<group name="eladmin,">
  <rule id="100823" level="12">
    <decoded>json</decoded>
    <field name="url">__generator__|__email__|__alipay__|__genconfig__</field>
    <description>ELADMIN: Low privilege user accessing admin-restricted controller endpoint (CVE-2026-77036)</description>
    <group>authentication_failure,</group>
    <mitre>
      <id>T1190</id>
    </mitre>
  </rule>
</group>

Mitigation & Patch Guidance

Patch Confidence: 0/4 — UNPATCHED

1. Immediate Mitigations (until patched):

   • Network Restriction: Place eladmin behind a VPN or internal network; do not expose it directly to the internet. Use firewall rules to restrict access to only authorized IP ranges.
   • Reverse Proxy Control: Configure a reverse proxy (Nginx/Apache) to block access to the affected endpoints unless the authenticated user is verified as admin via header injection or additional authentication layer.
   • Disable Affected Features: If the email, Alipay, or code generator features are not essential, disable them entirely via feature flags or Spring profile exclusion.
   • Monitor Privilege Escalation: Implement real-time alerts for any non-admin user accessing these four controller endpoints. Watch for unusual API patterns that loop through multiple controllers.
   • Session Hardening: Enforce strict session timeout and consider re-authentication for sensitive operations.

2. Patch/Upgrade Steps:

   • No official patch exists as of this writing. The vendor (elunez) has been notified via issue report but has not responded.
   • Monitor the official GitHub repository (github.com/elunez/eladmin) for a security release. Version 2.8 or later may include the fix.
   • As a stopgap, manually apply a code-level fix if you maintain the source: add Spring Security @PreAuthorize("hasRole('admin')") annotations to the affected controller methods (EmailController, AliPayController, GeneratorController, GenConfigController). Validate that each vulnerable endpoint enforces the admin role.

3. Long-Term Hardening:

   • Role-Based Access Control Audit: Conduct a comprehensive review of all controller endpoints in eladmin to ensure RBAC is enforced consistently. Look for missing @PreAuthorize or @Secured annotations.
   • Automated Security Testing: Integrate OWASP ZAP or Burp Suite into CI/CD pipelines to automatically test for broken access control (OWASP API Security Top 10 - Object Level Authorization).
   • Least Privilege Principle: Reduce the number of users with even low-level access to the system. Implement mandatory access controls where possible.
   • Web Application Firewall: Deploy a WAF with rules to detect and block access patterns matching the affected controller paths from non-admin sessions.
   • Dependency Security: Ensure the underlying Spring Security version is updated, as the root cause may stem from a configuration misconfiguration rather than a dependency flaw.

References

1. NVD Entry: https://nvd.nist.gov/vuln/detail/CVE-2026-77036 — Official CVE record with the described vulnerability information.
2. Vendor Repository: https://github.com/elunez/eladmin — Official eladmin source code repository. Monitor for security fix commits or release notes.
3. CWE-266 Reference: https://cwe.mitre.org/data/definitions/266.html — Incorrect Privilege Assignment weakness description.
4. CVSS Calculator: https://www.first.org/cvss/calculator/3.1#CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L — CVSS vector breakdown for this vulnerability.
5. CISA KEV: Not applicable — CVE-2026-77036 is not currently listed in the CISA Known Exploited Vulnerabilities catalog.

Threat Actor Activity: No specific threat actor campaigns have been publicly attributed to this CVE. However, the exploit is stated to be public, so the risk of opportunistic exploitation by threat actors is elevated. Given that eladmin is widely deployed in Chinese enterprises and the platform handles sensitive financial (AliPay) and infrastructure (code generation) functions, nation-state-adjacent actors with interest in Chinese corporate networks may leverage this vulnerability for intelligence or supply-chain compromise.