High
Security advisory
A security issue in nginx resolver was identified, which might allow an attacker who is able to forge UDP packets from the DNS server to cause 1-byte memory overwrite, resulting in worker process crash or potential other impact.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2021-23017
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 07:04 UTC · Revision 1
Source evidence
A security issue in nginx resolver was identified, which might allow an attacker who is able to forge UDP packets from the DNS server to cause 1-byte memory overwrite, resulting in worker process crash or potential other impact.
osv:CVE-2021-23017
Complete source record
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"title": "CVE-2021-23017",
"summary": "A security issue in nginx resolver was identified, which might allow an attacker who is able to forge UDP packets from the DNS server to cause 1-byte memory overwrite, resulting in worker process crash or potential other impact.",
"evidence": "osv:CVE-2021-23017",
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}
],
"source": "CPE_STRING"
}
]
},
{
"cpes": [
"cpe:2.3:a:oracle:enterprise_communications_broker:3.3.0:*:*:*:*:*:*:*"
],
"vendor_product": "oracle:enterprise_communications_broker",
"extracted_events": [
{
"range": [
{
"introduced": "3.3.0"
},
{
"last_affected": "3.3.0"
}
],
"source": "CPE_STRING"
}
]
},
{
"cpes": [
"cpe:2.3:a:oracle:enterprise_session_border_controller:8.4:*:*:*:*:*:*:*",
"cpe:2.3:a:oracle:enterprise_session_border_controller:9.0:*:*:*:*:*:*:*"
],
"vendor_product": "oracle:enterprise_session_border_controller",
"extracted_events": [
{
"range": [
{
"introduced": "8.4"
},
{
"last_affected": "8.4"
},
{
"introduced": "9.0"
},
{
"last_affected": "9.0"
}
],
"source": "CPE_STRING"
}
]
},
{
"cpes": [
"cpe:2.3:a:oracle:enterprise_telephony_fraud_monitor:3.4:*:*:*:*:*:*:*",
"cpe:2.3:a:oracle:enterprise_telephony_fraud_monitor:4.2:*:*:*:*:*:*:*",
"cpe:2.3:a:oracle:enterprise_telephony_fraud_monitor:4.3:*:*:*:*:*:*:*",
"cpe:2.3:a:oracle:enterprise_telephony_fraud_monitor:4.4:*:*:*:*:*:*:*"
],
"vendor_product": "oracle:enterprise_telephony_fraud_monitor",
"extracted_events": [
{
"range": [
{
"introduced": "3.4"
},
{
"last_affected": "3.4"
},
{
"introduced": "4.2"
},
{
"last_affected": "4.2"
},
{
"introduced": "4.3"
},
{
"last_affected": "4.3"
},
{
"introduced": "4.4"
},
{
"last_affected": "4.4"
}
],
"source": "CPE_STRING"
}
]
}
]
}
},
"related_cves": [
{
"value": "CVE-2021-23017",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 436703,
"published_at": "2021-06-01T13:15:07.853+00:00"
}