Vulnerability in F5 Nginx
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.
EPSS: 0.535 (98.9th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.7 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:L.
Affected products
- F5 Nginx
- Netapp Ontap_select_deploy_administration_utility
- Openresty
- Oracle Blockchain_platform
- Oracle Communications_control_plane_monitor — versions 3.4, 4.2, 4.3
- Oracle Communications_fraud_monitor
- Oracle Communications_operations_monitor — versions 3.4, 4.2, 4.3
- Oracle Communications_session_border_controller — versions 8.4, 9.0
- Oracle Enterprise_communications_broker — versions 3.3.0
- Oracle Enterprise_session_border_controller — versions 8.4, 9.0
Weakness classification (CWE)
Public proof-of-concept exploits
- M507/CVE-2021-23017-PoC
- 6lj/EVIL-CVE-2021-23017-Update-2025
- z3usx01/CVE-2021-23017-POC
- lakshit1212/CVE-2021-23017-PoC
- niandy/nginx-patch
- moften/CVE-2021-23017
- Cybervixy/Vulnerability-Management
- lukwagoasuman/-home-lukewago-Downloads-CVE-2021-23017-Nginx-1.14
- ShivamDey/CVE-2021-23017
- ChiomaDibor/Vulnerability-Management-of-a-Web-Server-Using-Nessus-and-Patch-Management-with-Ansible
References
- f5sirt@f5.com (x_refsource_MISC)
- f5sirt@f5.com (Patch, Mailing List, x_refsource_MISC, Vendor Advisory)
- f5sirt@f5.com (mailing-list, x_refsource_MLIST)
- f5sirt@f5.com (mailing-list, x_refsource_MLIST)
- f5sirt@f5.com (mailing-list, x_refsource_MLIST)
- f5sirt@f5.com (mailing-list, x_refsource_MLIST)
- f5sirt@f5.com (mailing-list, x_refsource_MLIST)
- f5sirt@f5.com (x_refsource_FEDORA, vendor-advisory)
- f5sirt@f5.com (x_refsource_FEDORA, vendor-advisory)
- f5sirt@f5.com (Patch, Third Party Advisory, x_refsource_MISC)
Frequently asked questions
- What is CVE-2021-23017?
- CVE-2021-23017 is a high-severity vulnerability in F5 Nginx, classified under Off-by-one Error. CVSS score: 7.7/10. Published 2021-06-01.
- How severe is CVE-2021-23017?
- High severity. CVSS v3 base score is 7.7 out of 10.
- Is CVE-2021-23017 known to be exploited?
- 86 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.