It’s a mystery … alleged unpatched Telegram zero-day allows device takeover, but Telegram denies

Pierluigi Paganini
March 30, 2026

A critical Telegram flaw could allow zero-click remote code execution on devices, but Telegram denies it.

Researcher Michael DePlante (@izobashi) of TrendAI Zero Day disclosed a new Telegram vulnerability through Zero Day Initiative (ZDI).

The vulnerability, tracked as ZDI-CAN-30207 (CVSS score of 9.8) allows attackers to execute code on targeted devices without any user interaction. This vulnerability is especially dangerous because an attacker can exploit it simply by sending a malicious animated sticker, with no action required from the victim. The vulnerability lies in how Telegram automatically processes media to generate previews, allowing crafted files to trigger code execution.

The flaw poses a serious security risk, especially as no patch is currently available, raising concerns across the cybersecurity community.

The vulnerability affects Telegram on Android and Linux; if exploited, it allows attackers to take full control of a device.

At this time it is unclear if threat actors have already exploited it in attacks in the wild.

The Zero Day Initiative did not disclose technical details about the vulnerability to give the company time to address it by July 24, 2026.

The Italian National Cybersecurity Agency (ACN) reported that Telegram has denied the disclosed zero-click vulnerability, stating it does not exist. The company says all stickers are validated server-side before delivery, preventing malicious files from being used as an attack vector and making code execution via stickers technically impossible.

“Following direct discussions, Telegram Messenger has formally denied the existence of the previously reported zero-click vulnerability, stating that the flaw does not exist. The vendor claims that every sticker uploaded…

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It’s a mystery … alleged unpatched Telegram zero-day allows device takeover, but Telegram denies