CVE-2021-23017

7.7HIGH

Key Information:

Vendor
F5
Status
Nginx Web Server, Nginx Plus
Vendor
CVE Published:
1 June 2021

Badges

👾 Exploit Exists🟡 Public PoC🟣 EPSS 43%

Summary

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.

Affected Version(s)

Nginx Web Server, Nginx Plus 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

Exploit Proof of Concept (PoC)

PoC code is written by security researchers to demonstrate the vulnerability can be exploited. PoC code is also a key component for weaponization which could lead to ransomware.

CVE-2021-23017-PoC
Created by M507

nginx-patch
Created by niandy

CVE-2021-23017-POC
Created by z3usx01

References

https://support.f5.com/csp/article/K12331123%2C
x_refsource_MISC
http://mailman.nginx.org/pipermail/nginx-announce/2021/00...
x_refsource_MISC
https://lists.apache.org/thread.html/r6fc5c57b38e93e36213...
mailing-listx_refsource_MLIST

EPSS Score

43% chance of being exploited in the next 30 days.

CVSS V3.1

Score:
7.7
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
High
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • 🟡

    Public PoC available

  • 👾

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

.