From 42f452626d0bcff9361a08c58877a9f2774a317e Mon Sep 17 00:00:00 2001
From: Henrique Pereira <ikkibr@gmail.com>
Date: Tue, 31 Mar 2026 09:32:09 -0600
Subject: [PATCH] Prevented Truncated Tag comparison

No minimum tag length was enforced. A user supplying a 1-byte tag only needed to match the first byte of the real tag, reducing the authentication check to a 1-in-256 brute-force
---
 cli/commands.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/cli/commands.c b/cli/commands.c
index 120a6fc..0696371 100644
--- a/cli/commands.c
+++ b/cli/commands.c
@@ -257,6 +257,10 @@ int verify(int argc, char **argv) {
   if (expected_tag_len > sizeof tag) {
     expected_tag_len = sizeof tag;
   }
+  if (expected_tag_len < sizeof tag) {
+    fputs("MAC tag verification failed\n", stderr);
+    goto out;
+  }
 
   // compare the tag
   if (CRYPTO_memcmp(expected_tag, tag, expected_tag_len) != 0) {