Google reCAPTCHA

reCAPTCHA is a Google service that protects your CAS deployment from spam and abuse. It uses advanced risk analysis techniques to tell humans and bots apart. CAS supports the reCAPTCHA API v2 and v3.

Support is enabled by including the following module in the WAR Overlay:

<dependency>
    <groupId>org.apereo.cas</groupId>
    <artifactId>cas-server-support-captcha</artifactId>
    <version>${cas.version}</version>
</dependency>

implementation "org.apereo.cas:cas-server-support-captcha:${project.'cas.version'}"

dependencyManagement {
    imports {
        mavenBom "org.apereo.cas:cas-server-support-bom:${project.'cas.version'}"
    }
}

dependencies {
    implementation "org.apereo.cas:cas-server-support-captcha"
}

dependencies {
    /*
    The following platform references should be included automatically and are listed here for reference only.
            
    implementation enforcedPlatform("org.apereo.cas:cas-server-support-bom:${project.'cas.version'}")
    implementation platform(org.springframework.boot.gradle.plugin.SpringBootPlugin.BOM_COORDINATES)
    */

    implementation "org.apereo.cas:cas-server-support-captcha"
}

The following settings and properties are available from the CAS configuration catalog:

_{The configuration settings listed below are tagged as Required in the CAS configuration metadata. This flag indicates that the presence of the setting may be needed to activate or affect the behavior of the CAS feature and generally should be reviewed, possibly owned and adjusted. If the setting is assigned a default value, you do not need to strictly put the setting in your copy of the configuration, but should review it nonetheless to make sure it matches your deployment expectations.}

cas.google-recaptcha.enabled=true

Whether google reCAPTCHA should be enabled.

org.apereo.cas.configuration.model.support.captcha.GoogleRecaptchaProperties.

_{How can I configure this property?}

Configuration properties can be included and activated using the following strategies.

:information_source: Note

When possible, properties should be stored in lower-case kebab format, such as cas.property-name=value. The only possible exception to this rule is when naming actuator endpoints; The name of the actuator endpoints (i.e. ssoSessions) MUST remain in camelCase mode.

CAS properties can be specified using the Java configuration property syntax in any and all .properties files:

cas.google-recaptcha.enabled=true

This is the most common form of property configuration that is recognized by CAS, regardless of the actual property source, which might in fact be managed separately outside the CAS environment, by another system or cloud framework.

CAS properties can be specified using the YAML syntax:

cas: 
  google-recaptcha: 
    enabled: 

Note that YAML is very specific about structure and indentation. Be sure to verify the correctness of the final result with your YAML validator of choice.

CAS properties can be passed to the CAS web application as system properties, when the application is launched:

java -Dcas.google-recaptcha.enabled="true" -jar build/libs/cas.war

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory. Note the placement of the system property which must be specified before the CAS web application is launched.

CAS properties can specified as system environment variables before the CAS web application is launched:

export CAS_GOOGLE_RECAPTCHA_ENABLED="true"

java -jar build/libs/cas.war

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

CAS properties can be passed to the CAS web application as command-line arguments, when the application is launched:

java -jar build/libs/cas.war --cas.google-recaptcha.enabled="true"

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

cas.google-recaptcha.score=0.5

reCAPTCHA v3 returns a score (1.0 is very likely a good interaction, 0.0 is very likely a bot). reCAPTCHA learns by seeing real traffic on your site. For this reason, scores in a staging environment or soon after implementing may differ from production. As reCAPTCHA v3 doesn't ever interrupt the user flow, you can first run reCAPTCHA without taking action and then decide on thresholds by looking at your traffic in the admin console. By default, you can use a threshold of 0.5.

org.apereo.cas.configuration.model.support.captcha.GoogleRecaptchaProperties.

_{How can I configure this property?}

Configuration properties can be included and activated using the following strategies.

:information_source: Note

CAS properties can be specified using the Java configuration property syntax in any and all .properties files:

cas.google-recaptcha.score=0.5

CAS properties can be specified using the YAML syntax:

cas: 
  google-recaptcha: 
    score: 

Note that YAML is very specific about structure and indentation. Be sure to verify the correctness of the final result with your YAML validator of choice.

CAS properties can be passed to the CAS web application as system properties, when the application is launched:

java -Dcas.google-recaptcha.score="0.5" -jar build/libs/cas.war

CAS properties can specified as system environment variables before the CAS web application is launched:

export CAS_GOOGLE_RECAPTCHA_SCORE="0.5"

java -jar build/libs/cas.war

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

CAS properties can be passed to the CAS web application as command-line arguments, when the application is launched:

java -jar build/libs/cas.war --cas.google-recaptcha.score="0.5"

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

cas.google-recaptcha.secret=

The google reCAPTCHA site secret.

org.apereo.cas.configuration.model.support.captcha.GoogleRecaptchaProperties.

_{How can I configure this property?}

Configuration properties can be included and activated using the following strategies.

:information_source: Note

CAS properties can be specified using the Java configuration property syntax in any and all .properties files:

cas.google-recaptcha.secret=...

CAS properties can be specified using the YAML syntax:

cas: 
  google-recaptcha: 
    secret: 

Note that YAML is very specific about structure and indentation. Be sure to verify the correctness of the final result with your YAML validator of choice.

CAS properties can be passed to the CAS web application as system properties, when the application is launched:

java -Dcas.google-recaptcha.secret="..." -jar build/libs/cas.war

CAS properties can specified as system environment variables before the CAS web application is launched:

export CAS_GOOGLE_RECAPTCHA_SECRET="..."

java -jar build/libs/cas.war

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

CAS properties can be passed to the CAS web application as command-line arguments, when the application is launched:

java -jar build/libs/cas.war --cas.google-recaptcha.secret="..."

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

cas.google-recaptcha.site-key=

The google reCAPTCHA site key.

org.apereo.cas.configuration.model.support.captcha.GoogleRecaptchaProperties.

_{How can I configure this property?}

Configuration properties can be included and activated using the following strategies.

:information_source: Note

CAS properties can be specified using the Java configuration property syntax in any and all .properties files:

cas.google-recaptcha.site-key=...

CAS properties can be specified using the YAML syntax:

cas: 
  google-recaptcha: 
    site-key: 

Note that YAML is very specific about structure and indentation. Be sure to verify the correctness of the final result with your YAML validator of choice.

CAS properties can be passed to the CAS web application as system properties, when the application is launched:

java -Dcas.google-recaptcha.site-key="..." -jar build/libs/cas.war

CAS properties can specified as system environment variables before the CAS web application is launched:

export CAS_GOOGLE_RECAPTCHA_SITE_KEY="..."

java -jar build/libs/cas.war

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

CAS properties can be passed to the CAS web application as command-line arguments, when the application is launched:

java -jar build/libs/cas.war --cas.google-recaptcha.site-key="..."

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

_{The configuration settings listed below are tagged as Optional in the CAS configuration metadata. This
flag indicates that the presence of the setting
is not immediately necessary in the end-user CAS configuration, because a default value is assigned or
the activation of the feature is not conditionally controlled by the setting value. You should only include this field in your
configuration if you need to modify the default value.}

cas.google-recaptcha.activate-for-ip-address-pattern=

A regular expression pattern to indicate that captcha should be activated when the remote IP address matches this pattern, and otherwise skipped and disabled.

org.apereo.cas.configuration.model.support.captcha.GoogleRecaptchaProperties.

_{How can I configure this property?}

Configuration properties can be included and activated using the following strategies.

:information_source: Note

CAS properties can be specified using the Java configuration property syntax in any and all .properties files:

cas.google-recaptcha.activate-for-ip-address-pattern=...

CAS properties can be specified using the YAML syntax:

cas: 
  google-recaptcha: 
    activate-for-ip-address-pattern: 

Note that YAML is very specific about structure and indentation. Be sure to verify the correctness of the final result with your YAML validator of choice.

CAS properties can be passed to the CAS web application as system properties, when the application is launched:

java -Dcas.google-recaptcha.activate-for-ip-address-pattern="..." -jar build/libs/cas.war

CAS properties can specified as system environment variables before the CAS web application is launched:

export CAS_GOOGLE_RECAPTCHA_ACTIVATE_FOR_IP_ADDRESS_PATTERN="..."

java -jar build/libs/cas.war

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

CAS properties can be passed to the CAS web application as command-line arguments, when the application is launched:

java -jar build/libs/cas.war --cas.google-recaptcha.activate-for-ip-address-pattern="..."

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

cas.google-recaptcha.invisible=false

Whether google reCAPTCHA invisible should be enabled.

org.apereo.cas.configuration.model.support.captcha.GoogleRecaptchaProperties.

_{How can I configure this property?}

Configuration properties can be included and activated using the following strategies.

:information_source: Note

CAS properties can be specified using the Java configuration property syntax in any and all .properties files:

cas.google-recaptcha.invisible=...

CAS properties can be specified using the YAML syntax:

cas: 
  google-recaptcha: 
    invisible: 

Note that YAML is very specific about structure and indentation. Be sure to verify the correctness of the final result with your YAML validator of choice.

CAS properties can be passed to the CAS web application as system properties, when the application is launched:

java -Dcas.google-recaptcha.invisible="..." -jar build/libs/cas.war

CAS properties can specified as system environment variables before the CAS web application is launched:

export CAS_GOOGLE_RECAPTCHA_INVISIBLE="..."

java -jar build/libs/cas.war

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

CAS properties can be passed to the CAS web application as command-line arguments, when the application is launched:

java -jar build/libs/cas.war --cas.google-recaptcha.invisible="..."

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

cas.google-recaptcha.position=bottomright

The google reCAPTCHA badge position (only if invisible is enabled). Accepted values are:

bottomright: bottom right corner, default value.
bottomleft: bottom left corner
inline: allows to control the CSS.

org.apereo.cas.configuration.model.support.captcha.GoogleRecaptchaProperties.

_{How can I configure this property?}

Configuration properties can be included and activated using the following strategies.

:information_source: Note

CAS properties can be specified using the Java configuration property syntax in any and all .properties files:

cas.google-recaptcha.position=bottomright

CAS properties can be specified using the YAML syntax:

cas: 
  google-recaptcha: 
    position: 

Note that YAML is very specific about structure and indentation. Be sure to verify the correctness of the final result with your YAML validator of choice.

CAS properties can be passed to the CAS web application as system properties, when the application is launched:

java -Dcas.google-recaptcha.position="bottomright" -jar build/libs/cas.war

CAS properties can specified as system environment variables before the CAS web application is launched:

export CAS_GOOGLE_RECAPTCHA_POSITION="bottomright"

java -jar build/libs/cas.war

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

CAS properties can be passed to the CAS web application as command-line arguments, when the application is launched:

java -jar build/libs/cas.war --cas.google-recaptcha.position="bottomright"

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

cas.google-recaptcha.verify-url=https://www.google.com/recaptcha/api/siteverify

The google reCAPTCHA endpoint for verification of tokens and input.

org.apereo.cas.configuration.model.support.captcha.GoogleRecaptchaProperties.

_{How can I configure this property?}

Configuration properties can be included and activated using the following strategies.

:information_source: Note

CAS properties can be specified using the Java configuration property syntax in any and all .properties files:

cas.google-recaptcha.verify-url=https://www.google.com/recaptcha/api/siteverify

CAS properties can be specified using the YAML syntax:

cas: 
  google-recaptcha: 
    verify-url: 

Note that YAML is very specific about structure and indentation. Be sure to verify the correctness of the final result with your YAML validator of choice.

CAS properties can be passed to the CAS web application as system properties, when the application is launched:

java -Dcas.google-recaptcha.verify-url="https://www.google.com/recaptcha/api/siteverify" -jar build/libs/cas.war

CAS properties can specified as system environment variables before the CAS web application is launched:

export CAS_GOOGLE_RECAPTCHA_VERIFY_URL="https://www.google.com/recaptcha/api/siteverify"

java -jar build/libs/cas.war

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

CAS properties can be passed to the CAS web application as command-line arguments, when the application is launched:

java -jar build/libs/cas.war --cas.google-recaptcha.verify-url="https://www.google.com/recaptcha/api/siteverify"

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

cas.google-recaptcha.version=GOOGLE_RECAPTCHA_V2

Indicate the version of the recaptcha api. Accepted values are: V2, V3. Available values are as follows:

GOOGLE_RECAPTCHA_V2: V2 version of the recaptcha API.
GOOGLE_RECAPTCHA_V3: V3 version of the recaptcha API.
HCAPTCHA: hCaptcha.

org.apereo.cas.configuration.model.support.captcha.GoogleRecaptchaProperties.

_{How can I configure this property?}

Configuration properties can be included and activated using the following strategies.

:information_source: Note

CAS properties can be specified using the Java configuration property syntax in any and all .properties files:

cas.google-recaptcha.version=GOOGLE_RECAPTCHA_V2

CAS properties can be specified using the YAML syntax:

cas: 
  google-recaptcha: 
    version: 

Note that YAML is very specific about structure and indentation. Be sure to verify the correctness of the final result with your YAML validator of choice.

CAS properties can be passed to the CAS web application as system properties, when the application is launched:

java -Dcas.google-recaptcha.version="GOOGLE_RECAPTCHA_V2" -jar build/libs/cas.war

CAS properties can specified as system environment variables before the CAS web application is launched:

export CAS_GOOGLE_RECAPTCHA_VERSION="GOOGLE_RECAPTCHA_V2"

java -jar build/libs/cas.war

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

CAS properties can be passed to the CAS web application as command-line arguments, when the application is launched:

java -jar build/libs/cas.war --cas.google-recaptcha.version="GOOGLE_RECAPTCHA_V2"

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.