CVE-2021-23017: Nginx Web Server, Nginx Plus

Affected products, as the CNA wrote them
Vendor	Product	Versions
Not given	Nginx Web Server, Nginx Plus	affected Nginx Web Server versions 0.6.18 thru 1.20.0 before 1.20.1, Nginx plus versions R13 thru R23 before R23 P1. Nginx plus version R24 before R24 P1

Not analysed yet

We haven’t published our own analysis of this CVE. If a person reviews it, this page will say what’s affected and what has to be true for it to matter.

Severity and exploitation

No source has published a CVSS score for this record yet.

CISA KEV Not listed.
EPSS 0.53, the 98th percentile, on 5 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

Timeline

This record came from the full history of the CVE Program, published 1 Jun 2021. New records show when each source confirmed them.

Sources

CVE List: CVE-2021-23017
NVD: CVE-2021-23017

References from the CNA

support.f5.com/csp/article/K12331123%2C
mailman.nginx.org/pipermail/nginx-announce/2021/000300.html
lists.apache.org/thread.html/r6fc5c57b38e93e36213e9a18c8a4e5dbd5ced1c7e57f08a1735975ba%40%3Cnotifications.apisix.apache.org%3E mailing-listmlist
lists.apache.org/thread.html/r37e6b2165f7c910d8e15fd54f4697857619ad2625f56583802004009%40%3Cnotifications.apisix.apache.org%3E mailing-listmlist
lists.apache.org/thread.html/rf318aeeb4d7a3a312734780b47de83cefb7e6995da0b2cae5c28675c%40%3Cnotifications.apisix.apache.org%3E mailing-listmlist
lists.apache.org/thread.html/r4d4966221ca399ce948ef34884652265729d7d9ef8179c78d7f17e7f%40%3Cnotifications.apisix.apache.org%3E mailing-listmlist
lists.apache.org/thread.html/rf232eecd47fdc44520192810560303073cefd684b321f85e311bad31%40%3Cnotifications.apisix.apache.org%3E mailing-listmlist
lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GNKOP2JR5L7KCIZTJRZDCUPJTUONMC5I/ vendor-advisoryfedora
lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/7SFVYHC7OXTEO4SMBWXDVK6E5IMEYMEE/ vendor-advisoryfedora
www.oracle.com/security-alerts/cpuoct2021.html
security.netapp.com/advisory/ntap-20210708-0006/ confirm
www.oracle.com/security-alerts/cpujan2022.html
www.oracle.com/security-alerts/cpuapr2022.html
packetstormsecurity.com/files/167720/Nginx-1.20.0-Denial-Of-Service.html

Facts on this page come from the CVE List as the CNA published them, with CVSS from the sources named above, CISA KEV and FIRST EPSS. Vendors, products and versions are shown as the CNA wrote them. We don’t reproduce the CVE’s description.