CVE-2026-94488

Telegram Desktop before 6.9.4 allows XSS in the HTML exporter. (The first fixed stable version is 7.0.1.) This occurs in button.text.toUtf8 in export_output_html.cpp. Exploitation cannot occur unless HTML export was used by a victim. However, the exploit payload can be exported if a message were forwarded into a group by a member (it is not necessary for the message author to be a member of a group).

CVSS v3 8.2 HIGH

8.2^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.8

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://expatch.com/writeups/telegram-html-export-xss.html
https://github.com/telegramdesktop/tdesktop/blob/v6.9.3/Telegram/SourceFiles/export/output/export_output_html.cpp
https://github.com/telegramdesktop/tdesktop/commit/52c779bffa8dde3c5c09826add2607328fae0924
https://github.com/telegramdesktop/tdesktop/commit/8457d13aa795fadf99c955d2a04f00ebc3c59df9
https://github.com/telegramdesktop/tdesktop/releases/tag/v6.9.4
https://thehackernews.com/2026/09/telegram-desktop-flaw-lets-hidden.html

Configurations

No configuration.

History

21 Sep 2026, 18:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-21 18:17

Updated : 2026-09-22 19:56

NVD link : CVE-2026-94488

Mitre link : CVE-2026-94488

CVE.ORG link : CVE-2026-94488

JSON object : View

Products Affected

No product.

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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