1 files changed, 1 insertions, 1 deletions
diff --git a/sid.ml b/sid.ml
index a2590fd..c6c7d3d 100644
--- a/sid.ml
+++ b/sid.ml
@@ -94,7 +94,7 @@ module StringFmt = struct
         let p = 4 in
         let p, ia = read_decimal_u64 s p in
         let sa = ref [] and p' = ref p in
-        while !p' < n && List.length !sa < max_subauth_count do
+        while !p' < n - 1 && List.length !sa < max_subauth_count do
           expect_char s '-' !p';
           let np, d = read_decimal_u32 s (!p' + 1) in
           sa := d :: !sa;