I found that some attackers are reportedly using custom UDP socket scripts and network packet tools during Telegram voice chats/groups to abuse network behavior and disrupt VC stability.
For example, I came across a simple UDP socket test script written in C language that sends packets over UDP (CoAP port testing). While this example itself is only a localhost test and not dangerous alone, similar modified scripts/tools can allegedly be abused by attackers for flooding or network-based disruption attempts.
Because of this abuse:
Group voice chats start lagging or glitching
Users get disconnected
VC becomes unstable or crashes
Communities are getting targeted repeatedly
Please investigate whether Telegram VC infrastructure has any vulnerability related to IP/network exposure or UDP abuse, and improve protection against such attacks.
This issue is actively affecting public groups and communities.
Steps to reproduce
Steps to reproduce:
Join or create a public Telegram group with Voice Chat enabled.
Start or join an active Voice Chat session.
After some time, malicious users begin targeting the VC using network/UDP abuse methods.
Voice Chat starts lagging, glitching, or disconnecting users.
Some users experience unstable audio, reconnect loops, or VC crashes.
Expected result:
Voice Chat should remain stable and protected against network abuse.
Actual result:
VC becomes unstable and users get disconnected due to possible abuse/exploit activity.
This issue is affecting multiple public groups. VC audio glitches, random disconnects, and crashes are happening frequently. Hope Telegram fixes this soon.
I already reported the DDoS issue to the Telegram team, but they still haven't fixed anything. This is really frustrating. Please fix it as soon as possible.
The issue is still reproducible as of September 2026. During active public Voice Chats, multiple participants can simultaneously become stuck on “Connecting…” or get disconnected. This continues despite restarting the Voice Chat and testing different networks/devices. Please investigate whether group Voice Chat participants can be exposed to direct UDP traffic or whether Telegram’s Voice Chat networking/relay infrastructure can be abused to cause packet flooding or connection disruption. Please also clarify whether there is an official way for group admins to force Voice Chats through Telegram relay infrastructure and prevent participant IP exposure.
QnA
The fix is usually closing the voice chat and reopening it.
Please investigate whether group Voice Chat participants can be exposed to direct UDP traffic or whether Telegram’s Voice Chat networking/relay infrastructure can be abused to cause packet flooding or connection disruption.
Please also clarify whether there is an official way for group admins to force Voice Chats through Telegram relay infrastructure and prevent participant IP exposure.