Source IP Spoofing Vulnerability in NGINX Plus and NGINX Open Source
CVE-2026-40460

6.9MEDIUM

Key Information:

Vendor

F5
Status
Nginx Plus
Nginx Open Source
Vendor
CVE Published:
13 May 2026

What is CVE-2026-40460?

A vulnerability has been identified in NGINX Plus and NGINX Open Source when the HTTP/3 QUIC module is enabled. An attacker could exploit this configuration to spoof their source IP address, potentially leading to a bypass of authorization mechanisms or the evasion of implemented rate limiting controls. This risk highlights the importance of maintaining proper security configurations and vigilance when utilizing advanced features like HTTP/3.

Affected Version(s)

NGINX Open Source 1.26.0 < 1.30.1

NGINX Plus R36

NGINX Plus R32

References

https://my.f5.com/manage/s/article/K000161068
vendor-advisorypatch

CVSS V4

Score:
6.9
Severity:
MEDIUM
Confidentiality:
Low
Integrity:
None
Availability:
Low
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

F5 acknowledges Rodrigo Laneth of Miralium Research for bringing this issue to our attention and following the highest standards of coordinated disclosure.
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