diff --git a/AFNetworking/AFURLConnectionOperation.m b/AFNetworking/AFURLConnectionOperation.m
index 4498513..dbc59a1 100644
--- a/AFNetworking/AFURLConnectionOperation.m
+++ b/AFNetworking/AFURLConnectionOperation.m
@@ -200,13 +200,13 @@ static BOOL AFSecKeyIsEqualToKey(SecKeyRef key1, SecKeyRef key2) {
     static NSArray *_pinnedCertificates = nil;
     static dispatch_once_t onceToken;
     dispatch_once(&onceToken, ^{
-        NSBundle *bundle = [NSBundle bundleForClass:[self class]];
-        NSArray *paths = [bundle pathsForResourcesOfType:@"cer" inDirectory:@"."];
-        
-        NSMutableArray *certificates = [NSMutableArray arrayWithCapacity:[paths count]];
-        for (NSString *path in paths) {
-            NSData *certificateData = [NSData dataWithContentsOfFile:path];
-            [certificates addObject:certificateData];
+        NSMutableArray *certificates = [NSMutableArray array];
+        for (NSBundle *bundle in [NSBundle allBundles]) {
+            NSArray *paths = [bundle pathsForResourcesOfType:@"cer" inDirectory:@"."];
+            for (NSString *path in paths) {
+                NSData *certificateData = [NSData dataWithContentsOfFile:path];
+                [certificates addObject:certificateData];
+            }
         }
         
         _pinnedCertificates = [[NSArray alloc] initWithArray:certificates];