Telegram Desktop Flaw Lets Attackers Steal Chat Messages Through Poisoned HTML Exports
Telegram Desktop XSS in bot inline keyboard buttons let attackers steal chat content from exported HTML archives; patched in 7.0.1.
ExPatch researchers Denis and Aleksander Rostilov found a stored cross-site scripting flaw in Telegram Desktop's HTML export feature, present since version 4.15.1 (March 2024). JavaScript hidden in bot inline keyboard button text executes when a user opens an exported chat HTML file with JavaScript enabled, exposing messages, metadata, and enabling DOM manipulation such as fake verification screens. Fixes shipped in Desktop Beta 6.9.4 (July 3, 2026) and Stable 7.0.1 (July 14, 2026), but previously exported HTML files remain unsafe.
Telegram Desktop Flaw Lets Hidden JavaScript Exfiltrate Messages From HTML Exports
Telegram Desktop HTML export XSS (CVSS 8.2) let bot messages exfiltrate exported chats; fixed in 7.0.1 but old exports stay vulnerable.
ExPatch researchers found that Telegram Desktop versions 4.15.1 (March 2024) through 6.9.3 wrote bot inline-keyboard button text into HTML chat exports without escaping, allowing a bot to plant invisible JavaScript. When a user opened the export in a browser, the script could exfiltrate every message in that 1,000-message file, rewrite the displayed content, or fake a verification form. The flaw (rated CVSS 3.1 8.2) was fixed by commit 8457d13a in 6.9.4 beta (July 3, 2026) and 7.0.1 stable (July 14, 2026), but pre-fix exports remain dangerous since updating the app does not fix old files. No CVE identifier or Telegram security advisory exists, and no exploitation in the wild is claimed.
CVE-2026-85630: HTML::FormHandler versions before 0.410002 for Perl render field attributes into HTML without escaping using the process_attrs method
CVE-2026-85630: HTML::FormHandler Perl versions before 0.410002 render field attributes into HTML unescaped, enabling HTML injection.
The Perl module HTML::FormHandler before version 0.410002 renders field attributes into HTML without escaping via the process_attrs method, per an oss-security disclosure. Applications using affected versions could allow unescaped markup to be injected into generated HTML. Users should upgrade to version 0.410002 or later.
CVE-2026-85485: HTML::FormHandler versions before 0.410002 for Perl render some error messages into HTML without escaping
HTML::FormHandler before 0.410002 for Perl renders error messages into HTML unescaped, enabling cross-site scripting (CVE-2026-85485); fixed in 0.410002.
Robert Rothenberg disclosed CVE-2026-85485 on the oss-security mailing list, affecting HTML::FormHandler versions before 0.410002 for Perl. The module renders some error messages into HTML without escaping, which can enable cross-site scripting in applications using its rendered output. The issue is fixed in version 0.410002.
CVE-2026-85484: HTML::FormHandler versions before 0.410002 for Perl render option group labels and radio button labels into HTML without escaping
HTML::FormHandler before 0.410002 for Perl renders option group and radio button labels unescaped into HTML, enabling XSS (CVE-2026-85484).
Robert Rothenberg disclosed CVE-2026-85484 on the oss-security mailing list, affecting HTML::FormHandler versions before 0.410002 for Perl. The module renders option group labels and radio button labels into HTML without escaping, which can enable cross-site scripting in applications using the rendered markup. The issue is addressed in version 0.410002.
Telegram Desktop XSS Vulnerability Lets Attackers Steal Entire Chat Histories
Stored XSS in Telegram Desktop HTML chat exports (CVSS 8.2) could let attacker-controlled inline keyboard buttons steal full chat histories.
ExPatch researchers Denis and Aleksander Rostilov found a stored XSS in Telegram Desktop's HTML chat export pipeline affecting builds before Beta 6.9.4 and Stable 7.0.1. Unsanitized inline keyboard button text becomes executable JavaScript when a user exports a chat and opens the HTML file in a browser, exposing messages, metadata, and local file paths, and enabling phishing overlays. Telegram patched the issue in commit 8457d13a during July 2026; no CVE had been assigned at disclosure time.
Telegram Desktop Flaw Could Turn Old Chat Exports Into Data Theft Traps
ExPatch disclosed stored XSS in Telegram Desktop HTML export letting bot messages steal chat data when exports open in browsers.
ExPatch researchers Denis and Aleksander Rostilov found a stored XSS flaw (CVSS 8.2) where bot inline keyboard button text was written unescaped into HTML chat exports, executing attacker JavaScript in browsers. The payload can persist in chat history for months, exfiltrate messages, metadata, and local file paths, and rewrite the page, spreading via forwarded messages without bot membership. Telegram fixed it by applying SerializeString(), first stable fixed release 7.0.1 shipped July 14, 2026, but HTML exports created with vulnerable versions remain dangerous.