Starting in Bug Bounty: Understanding 1-Day Vulnerabilities

Telegram for Android Patches Voice Call Vulnerability Enabling Code Execution

Security researchers at NebuSec disclosed a vulnerability in Telegram for Android that allowed remote code execution after a victim answered a voice call. The flaw affected versions from 8.6.2 through 12.10.3 and was fixed in release 12.10.4 at the end of September. The issue stemmed from improper handling of MediaState service messages that carry microphone, camera, and video rotation data during calls. When a required field was missing, the application accessed invalid memory. NebuSec discovered the bug using its Code Security product running on a GPT-5.4 model and confirmed exploitation on ARM64 Android devices for personal calls. A demonstration showed the string “HACKED BY NEBUSEC” appearing roughly 30 seconds after the call was accepted. The vulnerability is unrelated to the earlier animated-sticker attack vector.

Yandex Patches Millions of Stations After eMudhra Certificate Keys Compromised

Yandex has automatically deployed security updates to millions of its smart speakers and partner televisions running YaOS between October 21 and 23. The patches address compromised intermediate certificates issued by eMudhra whose private keys consisted of trivial values from 1 to 255. Attackers who obtained these keys could generate fraudulent certificates and perform man-in-the-middle attacks against device HTTPS traffic. Enthusiasts demonstrated that local network control combined with the certificates allowed replacement of server configuration, activation of ADB, and acquisition of root access on the devices. The update removes trust in the affected certificates, overwrites compromised system files, and disables the debug interface. A factory reset restores the vulnerable firmware, so Yandex advises against resets without a compelling reason.

Cisco ASA and FTD Face DoS Vulnerability in SSL VPN Already Exploited in the Wild

Cisco Systems has disclosed a denial-of-service vulnerability affecting its Cisco Secure Firewall ASA and Cisco Secure Firewall FTD products. The flaw, tracked as CVE-2026-76418, resides in the SSL VPN remote access feature and carries a CVSS v3.1 base score of 8.6, rated High severity. Exploitation occurs when secondary authentication is configured on tunnel groups, allowing an attacker to send a crafted request that forces a device reboot without requiring authentication. Cisco confirmed active exploitation of the issue in October 2026. Security updates addressing the vulnerability are now available for both affected product lines. The advisory recommends immediate application of the patches to prevent service disruption.