All vulnerabilities
CVE-2026-104939

NGINX Ingress Controller vulnerability

F5 NGINX Ingress ControllerWeb servers
CVSS
7.5High
ExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV
Exploit odds (EPSS)0.36%Chance of exploitation activity in the next 30 days, higher than 28% of CVEs. Scored 23 Oct 2026FIRST EPSS
Fixed in5.7.0Fixed versionCVE List
Published14 Oct 2026Updated 15 Oct 2026CVE List

What fixes it

A fixed version on one release line is not the upgrade target for every line. Check your exact version and any vendor backports.

Description

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.

Text from CVE List

Affected versions 1

  • NGINX Ingress Controlleraffected: 5.6.0 before 5.7.0CVE List

References 1