From e862798b9397c0fd9624025f010ca4165de2c0be Mon Sep 17 00:00:00 2001
From: Marc Bernard <marc@marcbernardtools.com>
Date: Tue, 7 Apr 2026 19:11:40 +0200
Subject: [PATCH] fixL `base64_decode` may consume invalid fourth symbol
 without rejecting

---
 index.js | 1 +
 1 file changed, 1 insertion(+)

diff --git a/index.js b/index.js
index 4a19b3d..c00dd01 100644
--- a/index.js
+++ b/index.js
@@ -490,6 +490,7 @@ function base64_decode(s, len) {
     if (++olen >= len || off >= slen) break;
     code = s.charCodeAt(off++);
     c4 = code < BASE64_INDEX.length ? BASE64_INDEX[code] : -1;
+    if (c4 == -1) break;
     o = ((c3 & 0x03) << 6) >>> 0;
     o |= c4;
     rs.push(String.fromCharCode(o));