CVE-2021-23017
HIGHCVSS 7.7/10EPSS 52.84%
Last modified
CVE-2021-23017 is a high-severity vulnerability rated 7.7/10 on the CVSS scale. 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.. EPSS estimates a 52.84% chance of exploitation in the next 30 days.
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.
Metrics
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:L
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| F5 | Nginx | >= 0.6.18, < 1.20.1 |
| Openresty | Openresty | < 1.19.3.2 |
| Fedoraproject | Fedora | 33 |
| Fedoraproject | Fedora | 34 |
| Netapp | Ontap Select Deploy Administration Utility | All versions |
| Oracle | Blockchain Platform | < 21.1.2 |
| Oracle | Communications Control Plane Monitor | 3.4 |
| Oracle | Communications Control Plane Monitor | 4.2 |
| Oracle | Communications Control Plane Monitor | 4.3 |
| Oracle | Communications Control Plane Monitor | 4.4 |
| Oracle | Communications Fraud Monitor | >= 3.4, <= 4.4 |
| Oracle | Communications Operations Monitor | 3.4 |
| Oracle | Communications Operations Monitor | 4.2 |
| Oracle | Communications Operations Monitor | 4.3 |
| Oracle | Communications Operations Monitor | 4.4 |
| Oracle | Communications Session Border Controller | 8.4 |
| Oracle | Communications Session Border Controller | 9.0 |
| Oracle | Enterprise Communications Broker | 3.3.0 |
| Oracle | Enterprise Session Border Controller | 8.4 |
| Oracle | Enterprise Session Border Controller | 9.0 |
| Oracle | Enterprise Telephony Fraud Monitor | 3.4 |
| Oracle | Enterprise Telephony Fraud Monitor | 4.2 |
| Oracle | Enterprise Telephony Fraud Monitor | 4.3 |
| Oracle | Enterprise Telephony Fraud Monitor | 4.4 |
| Oracle | Goldengate | < 21.4.0.0.0 |
References
- http://mailman.nginx.org/pipermail/nginx-announce/2021/000300.htmlMailing List, Patch, Vendor Advisory
- http://packetstormsecurity.com/files/167720/Nginx-1.20.0-Denial-Of-Service.htmlThird Party Advisory, VDB Entry
- https://security.netapp.com/advisory/ntap-20210708-0006/Third Party Advisory
- https://www.oracle.com/security-alerts/cpuapr2022.htmlPatch, Third Party Advisory
- https://www.oracle.com/security-alerts/cpujan2022.htmlPatch, Third Party Advisory
- https://www.oracle.com/security-alerts/cpuoct2021.htmlPatch, Third Party Advisory
- http://mailman.nginx.org/pipermail/nginx-announce/2021/000300.htmlMailing List, Patch, Vendor Advisory
- http://packetstormsecurity.com/files/167720/Nginx-1.20.0-Denial-Of-Service.htmlThird Party Advisory, VDB Entry
- https://security.netapp.com/advisory/ntap-20210708-0006/Third Party Advisory
- https://www.oracle.com/security-alerts/cpuapr2022.htmlPatch, Third Party Advisory
- https://www.oracle.com/security-alerts/cpujan2022.htmlPatch, Third Party Advisory
- https://www.oracle.com/security-alerts/cpuoct2021.htmlPatch, Third Party Advisory
Timeline
- Published
- Last Modified
- Status
- Modified
Frequently Asked Questions
What is CVE-2021-23017?
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.
How severe is CVE-2021-23017?
CVE-2021-23017 has a CVSS score of 7.7/10 (HIGH severity). The EPSS model estimates a 52.84% probability of exploitation in the next 30 days.
How do I fix CVE-2021-23017?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.
How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
- Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
- PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
- AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.
Related CVEs from 2021
- CVE-2021-23011On versions 16.0.x before 16.0.1.1, 15.1.x before 15.1.3, 14…7.5
- CVE-2021-23012On BIG-IP versions 16.0.x before 16.0.1.1, 15.1.x before 15.…8.2
- CVE-2021-23013On BIG-IP versions 16.0.x before 16.0.1.1, 15.1.x before 15.…7.5
- CVE-2021-23014On versions 16.0.x before 16.0.1.1, 15.1.x before 15.1.3, an…8.8
- CVE-2021-23015On BIG-IP 15.1.x before 15.1.3, 14.1.x before 14.1.4.2, 13.1…7.2
- CVE-2021-23016On BIG-IP APM versions 15.1.x before 15.1.3, 14.1.x before 1…5.3
- CVE-2021-23018Intra-cluster communication does not use TLS. The services w…7.4
- CVE-2021-23019The NGINX Controller 2.0.0 thru 2.9.0 and 3.x before 3.15.0 …7.8
- CVE-2021-2302Vulnerability in the Oracle Platform Security for Java produ…9.8
- CVE-2021-23020The NAAS 3.x before 3.10.0 API keys were generated using an …5.5
- CVE-2021-23021The Nginx Controller 3.x before 3.7.0 agent configuration fi…5.5
- CVE-2021-23022On version 7.2.1.x before 7.2.1.3 and 7.1.x before 7.1.9.9 U…7.8
Are you affected by CVE-2021-23017?
Run a free Strix scan to check your systems for this vulnerability.
Scan your code nowSource: NVD / NIST