Fatal Error: Call to a member function getGlobal() on null

Hi there –

My site started returning 500 results for every request with the following error and stack trace:

PHP Fatal error: Uncaught Error: Call to a member function getGlobal() on null in /wp-content/plugins/wordfence/vendor/wordfence/wf-waf/src/lib/rules.php:1809#012Stack trace:

012#0 /wp-content/plugins/wordfence/vendor/wordfence/wf-waf/src/lib/rules.php(1823): wfWAFRuleComparisonSubject->getRootValue('request.cookies')

012#1 /wp-content/plugins/wordfence/vendor/wordfence/wf-waf/src/lib/rules.php(1806): wfWAFRuleComparisonSubject->getValue()

012#2 /wp-content/plugins/wordfence/vendor/wordfence/wf-waf/src/lib/rules.php(1823): wfWAFRuleComparisonSubject->getRootValue(Object(wfWAFRuleComparisonSubject))

012#3 /wp-content/plugins/wordfence/vendor/wordfence/wf-waf/src/lib/rules.php(719): wfWAFRuleComparisonSubject->getValue()

012#4 /wp-content/plugins/wordfence/vendor/wordfence/wf-waf/src/lib/rules.php(1478): wfWAFRuleComparison->evaluate()

012#5 /wp-content/plugins/wordfence/vendor/wordfence/wf-waf/src/lib/rules.php(159): wfWAFRuleComparisonGroup->evaluate()

012#6 /wp-content/plugins/wordfence/vendor/wordfence/wf-waf/src/lib/waf.php(376): wfWAFRule->evaluate()

012#7 /wp-content/plugins/wordfence/vendor/wordfence/wf-waf/src/lib/waf.php(281): wfWAF->runRules()

012#8 /wp-content/plugins/wordfence/waf/bootstrap.php(985): wfWAF->run()

012#9 /wordfence-waf.php(10): include_once('/li…')

012#10 /usr/local/share/auto_prepends/auto_prepends.php(55): require_once('/li…')

012#11 {main}#012 thrown in /wp-content/plugins/wordfence/vendor/wordfence/wf-waf/src/lib/rules.php on line 1809

Can you please advise?