CVE-2026-40460: F5 NGINX Plus · Authentication Bypass by Spoofing
Affects F5 NGINX PlusSource CVE Database V5
Not known to be exploited · CVSS 6.5 Medium : upgrade to 1.30.1 when convenient.
Data as of 30 Oct 2026, 11:52 UTC
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 31% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 1.30.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:LExploitation evidence
Disclosed: evidence found.
CVE published 13 May 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.
What to do
Upgrade NGINX Open Source to 1.30.1.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| F5NGINX Plus | Affected
| Fixed in– |
| F5NGINX Open Source | Affected
| Fixed in
|
AI-suggested
If you cannot patch yet, organizations should consider disabling the HTTP/3 QUIC module if feasible or implementing additional network-level controls to detect and block IP spoofing.
Description
When NGINX Plus or NGINX Open Source are configured to use the HTTP/3 QUIC module, an attacker may be able to spoof their source IP address allowing for bypass of authorization or bypass of rate limiting. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.