diff --git a/CHANGELOG.md b/CHANGELOG.md
index de07e9c3b..e077339b6 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -12,6 +12,7 @@ All notable changes to this project will be documented in this file.
 ### Changed
 
 ### Fixed
+- Berry `bytes().asstring()` now truncates a string if buffer contains NULL
 
 ### Removed
 
diff --git a/lib/libesp32/berry/src/be_byteslib.c b/lib/libesp32/berry/src/be_byteslib.c
index d692286d9..046505aef 100644
--- a/lib/libesp32/berry/src/be_byteslib.c
+++ b/lib/libesp32/berry/src/be_byteslib.c
@@ -806,7 +806,8 @@ static int m_asstring(bvm *vm)
 {
     buf_impl attr = bytes_check_data(vm, 0);
     check_ptr(vm, &attr);
-    be_pushnstring(vm, (const char*) attr.bufptr, attr.len);
+    size_t safe_len = strnlen((const char*) attr.bufptr, attr.len);
+    be_pushnstring(vm, (const char*) attr.bufptr, safe_len);
     be_return(vm);
 }
 
diff --git a/lib/libesp32/berry/tests/bytes.be b/lib/libesp32/berry/tests/bytes.be
index 3533acc2a..6462fc1d0 100644
--- a/lib/libesp32/berry/tests/bytes.be
+++ b/lib/libesp32/berry/tests/bytes.be
@@ -354,3 +354,9 @@ assert(b.appendb64(c, 2) == bytes("AABBCC49673D3D"))
 b = bytes("AABBCC")
 assert(bytes().fromstring(bytes("11").tob64()) == bytes('45513D3D'))
 assert(b.appendb64(c, 1, 1) == bytes("AABBCC45513D3D"))
+
+#- asstring truncates if NULL is present -#
+s=bytes("414243").asstring()
+assert(size(s) == 3)
+s=bytes("410000").asstring()
+assert(size(s) == 1)