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.
Published · last modified .
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.
EPSS exploit prediction
EPSS: 0.535 (99.0th percentile), scored .
High probability of exploitation in the next 30 days — patch promptly. 99th percentile — 99.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.535 · newest: 0.535 · change: 0.000
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
- support.f5.com/csp/article/K12331123,
- mailman.nginx.org/pipermail/nginx-announce/2021/000300.html (Patch, Mailing List, Vendor Advisory)
- lists.apache.org/thread.html/r6fc5c57b38e93e36213e9a18c8a4e5dbd5ced1c7e57f08a17… (mailing-list)
- lists.apache.org/thread.html/r37e6b2165f7c910d8e15fd54f4697857619ad2625f5658380… (mailing-list)
- lists.apache.org/thread.html/rf318aeeb4d7a3a312734780b47de83cefb7e6995da0b2cae5… (mailing-list)
- lists.apache.org/thread.html/r4d4966221ca399ce948ef34884652265729d7d9ef8179c78d… (mailing-list)
- lists.apache.org/thread.html/rf232eecd47fdc44520192810560303073cefd684b321f85e3… (mailing-list)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
- www.oracle.com/security-alerts/cpuoct2021.html (Patch, Third Party Advisory)
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.