From 71b5e025903e2e6a7f4f2309a7e2930fed96fc0a Mon Sep 17 00:00:00 2001
From: Daniel Stenberg <daniel@haxx.se>
Date: Mon, 6 Oct 2025 16:10:27 +0200
Subject: [PATCH] mdlinkcheck: reject URLs containing quotes

Those would be illegal anyway and would make the script misbehave

Reported-by: Stanislav Fort
Closes #18889
---
 scripts/mdlinkcheck | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/scripts/mdlinkcheck b/scripts/mdlinkcheck
index 925edc5294..bbd6ac4602 100755
--- a/scripts/mdlinkcheck
+++ b/scripts/mdlinkcheck
@@ -140,6 +140,10 @@ sub checkurl {
     print "check $url\n";
     my $curlcmd="curl -ILfsm10 --retry 2 --retry-delay 5 -A \"Mozilla/curl.se link-probe\"";
     $url =~ s/\+/%2B/g;
+    if($url =~ /[\"\'\n]/) {
+        print STDERR "Bad URL in markdown: %s\n", $url{$url};
+        return 1; # fail
+    }
     my @content = `$curlcmd \"$url\"`;
     if(!$content[0]) {
         print STDERR "FAIL\n";