SunJSSE security provider cannot be properly initialized in FIPS mode from a configuration file. Initialization apparently succeeds but in non-FIPS mode.
In example, let's assume we have the following security providers in a 'java.security' configuration file:
security.provider.1=SunPKCS11 /path/to/nss.cfg
security.provider.2=com.sun.net.ssl.internal.ssl.Provider SunPKCS11-NSS
SunJSSE provider will be initialized in non-FIPS mode, as if the configuration line were "security.provider.2=com.sun.net.ssl.internal.ssl.Provider". In fact, you can set any invalid argument and initialization apparently succeeds because the argument is not considered at all.
This bug affects JDK-11 only. Newer versions are not affected because "Experimental FIPS support" was removed. Older versions are not affected because the code related to loading security providers is different.