CVE-2021-23017
HIGH
7.7
CVSS Score
Published: June 1, 2021 at 12:28 PM UTC
Updated: June 17, 2026 at 03:38 AM UTC
14 products affected across 5 vendorsFedoraONTAP Select Deploy administration utilityNGINX
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Severity
HIGH7.7
Exploit prediction
EPSS 53%
Description
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.
Affected
Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.
v < 1.20.10.6.18 ≤ v < 1.20.1
Affected range stops below 1.20.1, so it looks safe — our inference, not a vendor statement
All versions
v < 1.19.3.2
Affected range stops below 1.19.3.2, so it looks safe — our inference, not a vendor statement
95%
v < 21.1.2
Affected range stops below 21.1.2, so it looks safe — our inference, not a vendor statement
3.4 ≤ v ≤ 4.4
Remediation
No guide yetNo remediation guidance has been written for this CVE yet. What the record does show:
Patch and advisory references
- http://mailman.nginx.org/pipermail/nginx-announce/2021/000300.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/7SFVYHC7OXTEO4SMBWXDVK6E5IMEYMEE/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GNKOP2JR5L7KCIZTJRZDCUPJTUONMC5I/
- https://www.oracle.com/security-alerts/cpuapr2022.html
- https://www.oracle.com/security-alerts/cpujan2022.html
References (14)
x_refsource_MISCMailing ListPatchVendor Advisory
Source: [email protected]
http://mailman.nginx.org/pipermail/nginx-announce/2021/000300.htmlx_refsource_MISCThird Party AdvisoryVDB Entry
Source: [email protected]
http://packetstormsecurity.com/files/167720/Nginx-1.20.0-Denial-Of-Service.htmlVendor Advisoryx_refsource_FEDORA
Source: [email protected]
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/7SFVYHC7OXTEO4SMBWXDVK6E5IMEYMEE/CVSS
- Attack Vector
- NETWORK
- Complexity
- HIGH
- Privileges
- NONE
- User Interaction
- NONE
- Scope
- UNCHANGED
- Confidentiality
- HIGH
- Integrity
- HIGH
- Availability
- LOW
Vector?
Quick Info
StatusMODIFIED
CWE
CWE-193
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