Telegram Desktop through 2.4.3 does not require passcode entry upon pushing the Export key within the Export Telegram Data wizard. The threat model is a victim who has voluntarily opened Export Wizard but is then distracted. An attacker then approaches the unattended desktop and pushes the Export key. This attacker may consequently gain access to all chat conversation and media files.
https://security.gentoo.org/glsa/202101-34
https://github.com/telegramdesktop/tdesktop/releases/tag/v2.4.3
https://github.com/soheilsamanabadi/vulnerability/blob/main/Telegram-Desktop-CVE-2020-25824