diff --git a/base/stat.jl b/base/stat.jl
index f527664f228ad..35e02d2c373f9 100644
--- a/base/stat.jl
+++ b/base/stat.jl
@@ -327,10 +327,15 @@ This is the generalization of [`isfile`](@ref), [`isdir`](@ref) etc.
 """
 ispath(st::StatStruct) = filemode(st) & 0xf000 != 0x0000
 function ispath(path::String)
+    if contains(path, '\0')
+        throw(ArgumentError("embedded NULs are not allowed in C strings: \"$(repr(path))\""))
+    end
     # We use `access()` and `F_OK` to determine if a given path exists.
     # `F_OK` comes from `unistd.h`.
     F_OK = 0x00
-    return ccall(:jl_fs_access, Cint, (Ptr{UInt8}, Cint), path, F_OK) == 0
+    res = ccall(:jl_fs_access, Cint, (Ptr{UInt8}, Cint), path, F_OK)
+    @assert res in (0, Base.UV_ENOENT)
+    return res == 0
 end
 ispath(path::AbstractString) = ispath(String(path))