Skip to content

Prevent Url Fetch In Markdownify For Non Image Urls #915

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
ffrose merged 1 commit into from
Feb 10, 2026
Merged

Prevent Url Fetch In Markdownify For Non Image Urls #915

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
50 changes: 46 additions & 4 deletions GUI/src/components/Markdowify/index.tsx
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -7,6 +7,27 @@ interface MarkdownifyProps {
sanitizeLinks?: boolean;
}

const isValidImageUrl = (s: string): boolean => {
try {
const u = new URL(s);
if (!/^(https?|data):$/i.test(u.protocol)) return false;
if (s.startsWith('data:image/')) {
return /^data:image\/(png|jpe?g|gif|webp|svg\+xml|bmp);(base64,|charset=utf-8;)/i.test(s);
}
const path = u.pathname.toLowerCase();
const search = u.search.toLowerCase();
if (/\.(png|jpe?g|gif|webp|svg|ico|bmp|tiff?|avif|heic|heif|apng)([?#]|$)/i.test(path)) {
return true;
}
if (/\/(images?|img|photos?|pictures?|media|uploads?|thumb|avatar)\//i.test(path)) {
return true;
}
return /[?&](format|type|image|img|photo)=(png|jpe?g|gif|webp|svg|ico)/i.test(search);
} catch {
return false;
}
};

const LinkPreview: React.FC<{
href: string;
children: React.ReactNode;
Expand All @@ -27,6 +48,14 @@ const LinkPreview: React.FC<{
);
}

if (!isValidImageUrl(href)) {
return (
<a href={href} target="_blank" rel="noopener noreferrer">
{children}
</a>
);
}

return hasError ? (
<a href={href} target="_blank" rel="noopener noreferrer">
{children}
Expand All @@ -53,10 +82,22 @@ function formatMessage(message?: string): string {
.replaceAll(/\\?\$v\w*/g, '')
.replaceAll(/\\?\$g\w*/g, '');

return filteredMessage
.replaceAll(/&#x([0-9A-Fa-f]+);/g, (_, hex: string) => String.fromCharCode(parseInt(hex, 16)))
const dataImagePattern = /((?:^|\s))(data:image\/[a-z0-9+]+;[^)\s]+)/gi;
const finalMessage = filteredMessage.replaceAll(
dataImagePattern,
(_, prefix, dataUrl) => `${prefix}[image](${dataUrl})`,
);

return finalMessage
.replaceAll(/&#x([0-9A-F]+);/gi, (_, hex: string) => String.fromCharCode(parseInt(hex, 16)))
.replaceAll('&amp;', '&')
.replaceAll('&gt;', '>')
.replaceAll('&lt;', '<')
.replaceAll('&quot;', '"')
.replaceAll('&#39;', "'")
.replaceAll('&apos;', "'")
.replaceAll(/(^|\n)(\d{4})\.\s/g, (match, prefix, year) => {
const remainingText = filteredMessage.substring(filteredMessage.indexOf(match) + match.length);
const remainingText = finalMessage.substring(finalMessage.indexOf(match) + match.length);
const sentenceEnd = remainingText.indexOf('\n\n');
if (sentenceEnd !== -1) {
const currentSentence = remainingText.substring(0, sentenceEnd);
Expand All @@ -66,7 +107,8 @@ function formatMessage(message?: string): string {
}
return `${prefix}${year}\\. `;
})
.replace(/(?<=\n)\d+\.\s/g, hasSpecialFormat(filteredMessage) ? '\n\n$&' : '$&');
.replaceAll(/(?<=\n)\d+\.\s/g, hasSpecialFormat(finalMessage) ? '\n\n$&' : '$&')
.replaceAll(/^(\s+)/g, (match) => match.replaceAll(' ', '&nbsp;'));
}

const Markdownify: React.FC<MarkdownifyProps> = ({ message, sanitizeLinks = false }) => (
Expand Down