diff --git a/Lib/inspect.py b/Lib/inspect.py
index 36613160428..e60a235fe43 100644
--- a/Lib/inspect.py
+++ b/Lib/inspect.py
@@ -550,7 +550,7 @@ def findsource(object):
 
     file = getfile(object)
     sourcefile = getsourcefile(object)
-    if not sourcefile and file[0] + file[-1] != '<>':
+    if not sourcefile and file[:1] + file[-1:] != '<>':
         raise OSError('source code not available')
     file = sourcefile if sourcefile else file
 
diff --git a/Lib/test/test_inspect.py b/Lib/test/test_inspect.py
index 66ffe9133e8..6bd9bd1544f 100644
--- a/Lib/test/test_inspect.py
+++ b/Lib/test/test_inspect.py
@@ -416,6 +416,12 @@ def test_findsource_code_in_linecache(self):
         finally:
             del linecache.cache[co.co_filename]
 
+    def test_findsource_without_filename(self):
+        for fname in ['', '<string>']:
+            co = compile('x=1', fname, "exec")
+            self.assertRaises(IOError, inspect.findsource, co)
+            self.assertRaises(IOError, inspect.getsource, co)
+
 class TestNoEOL(GetSourceBase):
     def __init__(self, *args, **kwargs):
         self.tempdir = TESTFN + '_dir'
diff --git a/Misc/NEWS b/Misc/NEWS
index 5c2879ade9d..2af6102d996 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -297,6 +297,9 @@ Core and Builtins
 Library
 -------
 
+- Issue #17526: fix an IndexError raised while passing code without filename to
+  inspect.findsource().  Initial patch by Tyler Doyle.
+
 - Issue #17540: Added style to formatter configuration by dict.
 
 - Issue #16692: The ssl module now supports TLS 1.1 and TLS 1.2.  Initial