CVE-2021-23017

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.

Category

7.7
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 76.46% Top 5%
Vendor Advisory fedoraproject.org Vendor Advisory fedoraproject.org Vendor Advisory nginx.org
Affected: n/a Nginx Web Server, Nginx Plus
Published at:
Updated at:

References

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

Frequently Asked Questions

What is the severity of CVE-2021-23017?
CVE-2021-23017 has been scored as a high severity vulnerability.
How to fix CVE-2021-23017?
To fix CVE-2021-23017, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-23017 being actively exploited in the wild?
It is possible that CVE-2021-23017 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~76% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-23017?
CVE-2021-23017 affects n/a Nginx Web Server, Nginx Plus.
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