diff --git a/Model/Rule.php b/Model/Rule.php
index c888bcc..2317df0 100644
--- a/Model/Rule.php
+++ b/Model/Rule.php
@@ -121,7 +121,11 @@ private function scalarValueMatchesCondition(string $value, Condition $condition
 
         switch ($condition->type) {
             case 'regex':
-                return (bool)preg_match('/' . str_replace('/', '\/', $condition->value) . '/', $value);
+                $result = preg_match('/' . str_replace('/', '\/', $condition->value) . '/', $value);
+                if ($result === false) {
+                    $this->logPcreFailure($condition);
+                }
+                return (bool)$result;
             case 'contains':
                 return strpos($value, $condition->value) !== false;
             case 'equals':
@@ -131,6 +135,15 @@ private function scalarValueMatchesCondition(string $value, Condition $condition
         }
     }
 
+    private function logPcreFailure(Condition $condition): void
+    {
+        $this->logger->warning('Regex condition failed with a PCRE error.', [
+            'error' => function_exists('preg_last_error_msg') ? preg_last_error_msg() : preg_last_error(),
+            'target' => $condition->target,
+            'pattern' => $condition->value
+        ]);
+    }
+
     private function targetValueMatchesCondition($value, Condition $condition): bool
     {
         if ($condition->type === 'network') {
diff --git a/Test/Model/RuleTest.php b/Test/Model/RuleTest.php
index 0a3500c..4a1d661 100644
--- a/Test/Model/RuleTest.php
+++ b/Test/Model/RuleTest.php
@@ -146,6 +146,27 @@ public function testRuleWithMultipleConditions()
         $this->assertTrue($rule->matches($request));
     }
 
+    public function testRuleRegexLogsAndFailsOpenOnPcreError()
+    {
+        $originalBacktrackLimit = ini_get('pcre.backtrack_limit');
+        ini_set('pcre.backtrack_limit', '1');
+
+        try {
+            $logger = $this->createMock(Logger::class);
+            $logger->expects($this->once())->method('warning');
+            $request = $this->createConfiguredMock(Http::class, [
+                'getContent' => str_repeat('a', 50) . 'X'
+            ]);
+            $rule = new Rule(new IP(), $logger, 'block', [
+                new Condition('req.body', 'regex', '(a+)+$')
+            ]);
+
+            $this->assertFalse($rule->matches($request));
+        } finally {
+            ini_set('pcre.backtrack_limit', $originalBacktrackLimit);
+        }
+    }
+
     public function testRuleWithoutConditions()
     {
         $rule = new Rule(new IP(), $this->createMock(Logger::class), 'block', []);