Linux DoS Vulnerable Services Disabled Vulnerability

漏洞信息

漏洞名称： Linux DoS Vulnerable Services Disabled Vulnerability

漏洞类型： 配置问题

漏洞等级： 高危

漏洞描述： 该漏洞涉及Linux系统中的echo、discard、daytime和chargen等遗留服务。这些服务如果被启用，攻击者可能利用它们来提取系统信息或发起拒绝服务（DoS）攻击。这些服务在现代系统中通常不再需要，因此建议在不明确需要的情况下禁用它们。漏洞的技术根源在于这些服务的配置不当，即未正确设置为禁用状态。这可能导致系统面临信息泄露或服务不可用的风险。由于这些服务通常不需要认证即可访问，攻击者可以相对容易地利用它们进行攻击。此外，这种漏洞的利用可以自动化进行，增加了潜在的安全风险。因此，对于运行这些服务的系统，管理员应立即检查并禁用不必要的服务，以减少潜在的安全威胁。

产品名称： Linux

来源： https://github.com/projectdiscovery/nuclei-templates/blob/dfc176303ffebe3d9f231045fa3abe2cf2ca9874/misconfiguration%2Flinux%2Flinux-dos-vulnerable-services-disabled.yaml

类型： projectdiscovery/nuclei-templates:github issues

POC详情

id: linux-dos-vulnerable-services-disabled

info:
  name: DoS Vulnerable Services Disabled (echo, discard, daytime, chargen)
  author: songyaeji
  severity: high
  description: >
    If services such as echo, discard, daytime, and chargen are enabled on the system, 
    attackers may exploit them to extract system information or launch denial-of-service (DoS) attacks. 
    These legacy services should be disabled if not explicitly required.
  reference:
    - https://isms.kisa.or.kr
    - Cloud Vulnerability Assessment Guide(2024) by KISA
  tags: linux,misconfiguration,xinetd,DoS,legacy
  metadata:
    verified: true
    os: linux
    max-request: 1
  classification:
    cvss-metrics: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
    cvss-score: 5.5
    cwe-id: CWE-284

self-contained: true

code:
  - engine:
      - bash
    source: |
      vulnerable=""
      for svc in echo discard daytime chargen; do
        if grep -iq 'disable[[:space:]]*=[[:space:]]*no' "/etc/xinetd.d/$svc" 2>/dev/null; then
          echo "[VULNERABLE] $svc service is enabled in /etc/xinetd.d/$svc"
          vulnerable="yes"
        fi
      done

      if [ -z "$vulnerable" ]; then
        echo "[SAFE] All DoS-related services are properly disabled"
      fi
    matchers:
      - type: word
        part: code_1_response
        words:
          - "[VULNERABLE]"