CVE-2026-104939 (GCVE-0-2026-104939)

Vulnerability from cvelistv5 – Published: 2026-10-14 14:40 – Updated: 2026-10-15 16:43
VLAI
Title
NGINX Ingress Controller vulnerability
Summary
Description NGINX Ingress Controller has a vulnerability when implementing an externalAuth policy for ingress. NGINX Ingress Controller may mishandle the HTTP response from an OAuth IdP and allow an attacker to acquire unauthenticated access to protected paths before the proper external authentication can happen. Impact This vulnerability may allow remote attackers unauthenticated access to protected paths. There is no control plane exposure; this is a data plane issue only. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
8.7 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-15 15:54 UTC
CWE
Assigner
f5 CNA under the mitre root
CNA scorecard B 84/100 over 87 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
F5 NGINX Ingress Controller Affected: 5.6.0 , < 5.7.0 (custom)
guessed Create a notification for this product.
Date Public
2023-01-01 00:00
Credits
F5 acknowledges Carl Liljencrantz for bringing this issue to our attention and following the highest standards of coordinated disclosure.
Show details on NVD website
To clipboard 

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